Phase Diagrams of Binary Mixtures of Saturated Monoglycerides in Vegetable and Mineral Oil and Their Impact in the Oleogels Rheology

Phase Diagrams of Binary Mixtures of Saturated Monoglycerides in Vegetable and Mineral Oil and Their Impact in the Oleogels Rheology | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Phase Diagrams of Binary Mixtures of Saturated Monoglycerides in Vegetable and Mineral Oil and Their Impact in the Oleogels Rheology Maria E. Charó-Alvarado, Miriam A. Charó-Alonso, J. F. Toro-Vazquez This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3928380/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 7 You are reading this latest preprint version Abstract Phase diagrams of binary mixtures of 1-stearoyl glycerol (C18) with 1-myristoyl glycerol (C14), 1-palmitoyl glycerol (C16) or 1-monobehenin glycerol (C22) in vegetable and mineral oil were obtained using different molar fractions of the monoglycerides (MGs) keeping the MG concentration constant (8% wt/wt). We observed that, independent of the MG mixture (C18:C14, C18:C16, C18:C22) and the type of oil, the MGs developed a mixed La phase with a transition temperature practically independent of the C18 molar fraction. In contrast, the transition temperature for the sub-α phase showed a eutectic point that, for the same MG mixture, occurred in both oils at the same MG molar fraction. At the MG molar composition corresponding to the eutectic point, the difference in length between the aliphatic chains in the mixed lamella resulted in a sub-α phase with the least efficient chain packing of that developed by any other MG molar fraction. Independent of the MG mixture and the type of oil, the oleogels developed by cooling (80°C to 5°C) vegetable and mineral oil MG solutions followed by 180 min at 5°C achieved the highest elasticity (G’5°C) at the MG molar fraction composition associated with the eutectic point. Tentatively the least efficient aliphatic chains packing developed by the sub-α phase at the eutectic point, favored the incorporation and retention of higher amounts of oil. Thus, for a particular MG binary mixture, the oleogels at the eutectic point had the highest G’5°C in comparison with the G’5°C of oleogels formulated at any other MG proportion. Saturated Monoglycerides Phase Diagrams Oleogels rheology Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 1. INTRODUCTION Molecular gels, also known as organogels or oleogels (i.e., organogels when the liquid phase is vegetable or mineral oil) is a particular class of gel composed of an organic solvent physically trapped within a supramolecular structure developed through the spontaneous self-assembly of low molecular weight (< 3000 Da) molecules (i.e., gelator molecules). The molecular self-assembly usually occurs at temperatures below the gelator’s solubility limit in the solvent (i.e., the vegetable or mineral oil). The potential use of oleogels developed with edible oils resides in their use as replacement of the solid phase provided by saturated and trans fats to different food systems (i.e., margarines, confectionery, and table spreads, shortennings). On the other hand, we can also develop oleogels with useful and novel functional properties for the cosmetics industry [ 1 ], where mineral oil is a solvent commonly used in the formulation of these products [ 2 ]. In any case, the rheological properties of the oleogels are of utmost importance in determining relevant functional properties of food products and cosmetics like texture and oil binding capacity [ 3 – 4 ] The molecular self-assembly that upon cooling follows common lipophilic gelator (i.e., n alkanes, fatty acids, long chain esters, 12-hydroxysteaic acid) in vegetable or mineral oil solutions for the development of oleogels shows just one major sol → gel transition. In contrast, the organogelation of amphipathic molecules like phospholipids (i.e., lecithin) and monoglycerides (MGs) in oil solution show the development of several mesophase structures derived from the polar and the hydrophobic character of their chemical structure and functional groups (i.e., OH and phosphate groups, alkyl chains). The interactions of these functional groups with the oil determine the gelator-gelator and the gelator-solvent interactions, and subsequently whether the gelator would be soluble (i.e., no gelation), not soluble (i.e., the gelator precipitates) in the oil, or able of developing a supramolecular structure that physically traps the oil forming a self-supporting structure [ 5 ]. In the case of the monoglycerides (MGs), upon cooling MGs oil solutions at low concentration (i.e., < 1%) from the isotropic phase, the monoglycerides develop micelles with an inverse organization. In contrast, at concentrations above the critical micelle concentration the MGs directly develop inverse lamellar bilayer structures (i.e., the Lα mesophase). In the inverse Lα phase the polar “head” groups are closely packed in a bilayer organization with the aliphatic “tails” pointing toward the oil phase. Upon further cooling, the aliphatic chains of the MGs crystallize developing the sub-α phase. Our initial studies with vegetable oil solutions of a neat MG (i.e., 1-mono-stearyloyl-glycerol) and a commercial MG (i.e., a mixture of 1-mono-stearyloyl-glycerol and 1-mono-palmitoyl-glycerol) showed the Lα and the sub-α phases form the microstructure that provides the thermo-mechanical properties of MG oleogels [ 6 ]. Additionally, the initial studies of Lutton showed that only in MGs with esterified fatty acids longer than 16 carbons an additional transition occurs at lower temperatures than the Lα → sub-α transition (i.e., the sub-α2 phase) [ 7 ]. However, a recent study showed that the sub-α2 phase can also be developed by MGs with esterified fatty acids of 16 carbons [ 8 ]. The sub-α1 → sub-α2 transition might to be associated with the crystallization of a rotator phase remnant after the initial crystallization of the aliphatic chains in the Lα phase of the MGs [ 9 , 8 ]. The flow properties of various phase-change materials used in energy storage, the formation of superhydrophobic and self-healing cuticle layers in plants and insects, and the rheological and textural properties of foods and cosmetic products have been associated with the temperature interval where the crystallization↔melting of rotator phases occurs [ 10 – 11 ]. Then upon applying cooling-heating cycles to neat samples or vegetable and mineral oil solutions of MGs with esterified fatty acids of 16 carbons or longer, the order of the reversible phase transitions is Lα ⇄ sub-α1 ⇄ sub-α2. Within this context, the phase diagrams are used to describe the phases occurring and coexisting during molecular self-assembly and subsequent crystallization of pure gelators, gelator solutions or organogels (i.e., MGs oleogels). This, as a function of temperature and gelator concentration, assuming sufficient time and energy to achieve thermodynamic equilibrium conditions are provided [ 12 ]. To evaluate the practical use of MG oleogels is important to establish the relationship between the MGs’ phase diagrams in vegetable and mineral oils and the corresponding oleogel’s rheological properties. This since the viscoelastic properties of the MG oleogels are essential in the production of trans -free substitutes for food systems and the manufacture of cosmetics with useful and novel functional properties. In the food and cosmetic industry saturated monoglycerides are commonly used at high purity (i.e., ≥ 90%) as distilled MGs or as a mixture of MGs where C18 is usually one component. Within the previous framework the present study established the phase diagrams of mixtures of rac -1-stearoyl glycerol (C18) with different proportions of rac -1-myristoyl glycerol (C14), rac -1-palmitoyl glycerol (C16) or 1-monobehenin glycerol (C22) in vegetable and mineral oil. The phase diagrams of the MGs mixtures were elaborated at different molar fractions keeping the total concentration of MGs at 8% (wt/wt). Acknowledgment of the phase diagrams of amphipathic gelator molecules (i.e. pure MG solutions and MGs mixture solutions) are a major step in developing any industrial application. Additionally, at some molar fractions used in the elaboration of the phase diagrams, specifically including the MGs mixture where we observed the eutectic temperature, we evaluated the evolution of the rheology during the development of the MGs oleogel (i.e., cooling from 80°C to 5°C) and of the MGs oleogel under isothermal conditions (i.e., 3 h at 5°C). A eutectic system is a mixture of at least two components (i.e., two MGs) that has a melting temperature lower than any of the constitutive compounds. [ 13 – 15 ]. There is no information regarding the rheological behavior of oleogels developed with eutectic mixtures of MG. This information would be relevant for the industrial application of MG oleogels, mainly because eutectic mixtures usually crystallize as one common crystal developing systems with physical properties that cannot be obtained with other non-eutectic mixtures (i.e., enhanced rheological properties, no phase separation, smaller crystal size distribution) [ 16 – 18 ]. 2. MATERIALS AND METHODS 2.1. Materials The vegetable oil used was a refined, bleached, and deodorized high oleic safflower oil obtained from a local distributor (Coral Internacional, San Luis Potosí, México). Its detailed composition of triacylglyceride (TAGS) was previously reported [ 8 ], showing that the major TAGS were OOO (65.65% ± 0.15%), LOO (16.26% ± 0.04), and POO (8.58% ± 0.04) (O = oleic acid; L = linoleic acid; P = palmitic acid). The mineral oil was constituted, according to the manufacturer (Hycel de México, Jal., México), by a mixture of long chain alkanes. The rac -1-myristoyl glycerol (C14), rac -1-palmitoyl glycerol (C16), and rac -1-stearoyl glycerol (C18) were obtained from Sigma-Aldrich (St. Louis, MO), and the 1-monobehenin glycerol (C22) from INDOFINE Chemical Company Inc. (Hillsborough, NJ). According to the manufacturers the MGs had a purity above 99%. 2.2. Differential scanning calorimetry analysis of the mixtures of MGs in the VO and MO In 12 x 35 mm glass vials we prepared vegetable and mineral oil solutions of MGs mixtures (i.e., C18:C14, C18:16, and C18:C22) always keeping a total MG concentration of 8% (wt/wt). The proportions of C18 to C14, C16 or C22 in each type of oil were 8:0, 7:1, 6:2, 5:3, 4:4, 3:5, 2:6.1:7, and 0:8 (wt%:wt%), corresponded to molar fractions of C18 in each MG mixture of 1.0, 0.875, 0.75, 0.625, 0.50, 0.375, 0.25, 0.125, and 0.0, respectively. Likewise, the C18 to C14, C16 or C22 proportions studied corresponded to molar fractions of C14, C16 or C22 in each MG mixture of 0.0, 0.125, 0.25, 0.375, 0.50 0.625, 0.75, 0.875, and 1.0. To achieve full solubility of the MGs the C18:C14 and C18:16 dispersions were heated at 85°C for 20 min, and the C18:C22 to 95°C for 20 min with intermittent gently stirring. Then, the vials with the MG mixtures oil solution were allowed to cool at room temperature (≈ 20°C) and subsequently stored at 5°C. Samples (≈ 10–15 mg) of the VO and MO solutions of the MG mixtures were sealed in Tzero aluminum pans (of a maximum volume of 20 µL), heated at 90°C for 20 min and then cooled to -20°C at 10°C/min in a DSC (Q2000, TA Instruments; New Castle, DL). After 2 min at this temperature the system was heated at 5°C/min until reached 85°C. Using the first derivative of the heat flow as a function of temperature obtained with the equipment software (Universal Analysis 2000 v 4.5 built 4.5.0.5, TA Instruments; New Castle, DL), we determined the crystallization temperature (T Cr ) at the minimum heat flow of the different phase transitions observed in the cooling thermograms. In the same way, we determined the melting temperature (T M ) at the maximum heat flow of the endotherms associated with the phase transitions observed in the heating thermograms. The phase diagrams for each MG mixture in the VO and MO solution were established based on the crystallization and melting thermograms, and on the phase diagrams for the pure MG oil solutions previously recently published [ 8 ]. 2.3. Rheology measurements of the MG mixtures At particular molar fractions of C18 in the mixture with C14, C16, and C22 (i.e., 1.0, 0.875, 0.50, 0.125, 0.0 and the corresponding molar fraction at the eutectic point of the C18:C14, C18:16, and C18:C22 mixture), we evaluated the rheological properties of the MG mixtures in the oil using a Discovery HR3 rheometer (TA-Instruments; New Castle, DL, USA) equipped with a sand-blasted parallel plate-plate geometry (model 105670, 25 mm diameter) and a true-gap system. The temperature was controlled with a Peltier system located on the base of the geometry additionally supported with a ThermoCube Liquid-Liquid recirculating chiller system (Solid state cooling system; Wappingers Falls, NY, USA). The rheometer was controlled through the equipment software (Trios V 3.0.0.3156, TA Instruments-Waters LLC, New Castle, D. E.). A sample of the corresponding MG mixture solution was preheated at 80°C and applied on the base of the geometry that was pre-set at 80°C, then, using the true gap function, the plate of the geometry was set on the sample surface at the initial gap position in 300 µm. After stabilizing the sample temperature for 20 min at 80°C, the system was cooled at 10°C/min until achieving 5°C while measuring the elastic (G′) and loss (G″) modulus. Then we continued measuring G’ and G” under isothermal conditions (5°C) during 3 h, always applying conditions within the linear viscoelastic region (LVR) of the system. The LVR conditions were previously determined from strain (γ) sweeps obtained over the entire temperature interval (80°C to 2°C) applying a frequency of 1 Hz. 2.4. Statistical analysis The effect of the treatment conditions on the thermal and rheological properties evaluated was analyzed through ANOVA and contrast between the treatment means using the STATISTICA V 12 (StatSoft Inc., Tulsa, OK). 3. RESULTS AND DISCUSION The phase diagrams for the C18:C14, C18:C16, and the C18:C22 mixtures in vegetable and mineral oil are shown in Figs. 1 and 2 , respectively. As stated in the methodology, the phase diagrams for the MG binary mixtures in each type of oil were constructed as a function of both, the molar fractions of C18 and the corresponding molar fractions of C14, C16 or C22 in the MG mixture (Figs. 1 and 2 ). The behavior of the phase diagrams was established based on the corresponding crystallization and melting thermograms for the C18:C14, C18:C16, and the C18:C22 mixtures in the vegetable and the mineral oil (shown in Figs. 1SM to 3SM), and on the phase diagrams for MG oil solutions recently reported by our group [ 8 ]. 3.1 Phase transitions of the C14, C16, C18, and C22 oil solutions at a molar fraction of 1.0 Under the cooling-heating conditions used in this study the thermograms of the 8% vegetable and mineral oil solutions of C16, C18, and C22 (i.e., corresponding to a molar fraction of 1.0 for C16, C18, and C22) showed the reversible Lα ⇄ sub-α1 ⇄ sub-α2 phase transitions (Figs. 1SM to 3SM). In line with our previous study [ 8 ], the sub-α2 phase transition occurred just in the vegetable or mineral oil solutions of MGs with esterified fatty acids of 16 or more carbons. The sub-α2 phase did not occur during the cooling of the vegetable or mineral oil solutions of the binary mixtures of C16, C18, and C22 studied. Somehow the development of a mixed lamellar structure by the binary mixture of MGs limited the formation of the sub-α2 phase ( vide infra ). The temperature for the sub-α2 phase transition in the vegetable oil, indicated with an arrow in the corresponding phase diagrams at 1.0 molar fraction for C16, C18, and C22 (Fig. 1 ), was 21.02°C (± 0.11°C), 23.22°C (± 0.03°C), and 48.64°C (± 1.07°C), respectively. In the mineral oil the sub-α2 phase transition temperature for the 1.0 molar fraction of C16, C18, and C22 occurred at lower temperatures (P < 0.05), specifically at 17.79°C (± 0.31°C), 20.50°C (± 0.08°C), and 41.50°C (± 1.69°C), respectively. As previously stated, the sub-α1 → sub-α2 transition seems to be associated with the crystallization of a rotator phase remnant after the initial crystallization of the aliphatic chains in the Lα phase of the MGs [ 8 , 9 ]. Our results indicated that, in the mineral oil the crystallization of the remnant rotator phase for the development of the sub-α2 phase by the C16, C18, and C22, required higher supercooling than in the vegetable oil. In contrast to the behavior observed with C16, C18, and C22 oil solutions at 1.0 molar fraction, the cooling and heating thermogram for the C14 solution in both types of oils just showed the development of the isotropic ⇄ Lα ⇄ sub-α transitions. However, it is important to note that the heating thermogram for the C14 at 1.0 molar fraction in vegetable oil showed the presence of a small additional endotherm at a temperature above the endotherm associated with the Lα phase (Fig. 1 SM, panel B). This endotherm was present in the C14 mineral oil solution at 1.0 molar fraction (i.e., 0:8 C18:C14 mixture), and particularly evident in the 7:1 and 6:2 C18:C14 mixtures also (Fig. 1 SM, panel D). Based on studies done by Lutton [ 7 ], Malkin and Shurbagy [ 19 ] and our previous results with neat C14 and C14 oil solutions [ 8 ], the endotherm observed in the vegetable and mineral oil solutions of the 0:8 binary mixture of C18:C14 (i.e., 1.0 molar fraction) was associated with the melting of a β phase. This β phase ought to be developed during the cooling/heating conditions applied from C14 through a sub-α to β polymorphic transition [ 6 , 20 , 21 ]. Since the development of the β phase in the 0:8 binary mixture of C18:C14 (and in the 7:1 and 6:2 C18:C14 binary mixtures; see further discussion) came from a polymorphic transition, the development of the β phase was not included in the corresponding phase diagrams. 3.2. Phase transitions of the C18:C14, C18:C16, and C18:C22 binary mixtures. Independent of the type of oil used, under the cooling-heating conditions applied the cooling and heating thermograms for the C18:C14, C18:C16 and the C18:C22 mixtures at the 7:1, 6:2, 5:3, 4:4, 3:5, 2:6, and 1:7 proportions (i.e., corresponding to molar fractions of C18 lower than 1.0) showed the crystallization exotherms and corresponding melting endotherms associated just with the Lα and the sub-α transitions (Figs. 1SM to 3SM). The presence of just one crystallization exotherm and melting endotherm associated with the Lα phase transition, indicated that upon cooling from the isotropic phase the binary mixtures of MGs (i.e., C18:C14, C18:C16 and C18:C22) developed a mixed lamellar organization (i.e., the Lα phase). Upon further cooling the mixed Lα phase developed the sub-α phase (i.e., the sub-α1 phase) through the crystallization of the alkyl chains in the mixed lamella. Nevertheless, the corresponding thermograms of the binary mixtures in the vegetable and mineral oil did not show the development of the sub-α2 phase at any of the proportions studied (Figs. 1SM to 3SM). As already stated, the development of mixed lamellar structures by the C18:C14, C18:C16 and C18:C22 binary mixtures somehow limited the formation of the sub-α2 phase. As already indicated, independent of the type of oil, the heating thermograms of the C18:C14 binary mixture at 7:1 and 6:2 proportions (Fig. 1SM panels B and D), showed an additional endotherm above the melting endotherm for the Lα phase. Additionally, at the 5:3 and 4:4 proportions we noted that the melting endotherm for the Lα phase showed a shoulder (Fig. 1SM panel B). This behavior was associated with the melting of a β phase, tentatively developed through a polymorphic transition from the sub-α phase of C18 [ 21 – 22 ]. Within this context, we considered that in the vegetable oil the C18:C14 system at the 7:1, 6:2, 5:3 and 4:4 proportions the melting of the Lα and the β phases occurred within the same temperature interval making hard to establish a reliable phase transition for the Lα phase. Consequently, the phase diagram for the C18:C14 in the vegetable oil could not include a phase transition temperature for the Lα phase for the whole concentration interval studied (Fig. 1 A). Therefore, in the phase diagram for the C18:C14 in the vegetable oil (Fig. 1 A) the Lα phase transition temperature tentatively occurring at C18 molar fractions higher than 0.4 (i.e., C14 molar fractions lower than 0.6) was indicated just with a dotted line. As established by Lutton [ 7 ] and our own studies [ 8 ], C14 is prone to go through a sub-α to β polymorphic transition in the neat state and in oil solutions. Additionally, Chen and Terentjev [ 22 ] observed that after 5–7 days of storage at 26°C neat C18 developed a β polymorph also through a polymorphic transition from the sub-α phase. Then, the results obtained indicated that in the 7:1, 6:2, 5:3 and 4:4 C18:C14 binary mixtures the presence of C14 in the mixed lamella could promote the development of the β phase from the C18, particularly in the vegetable oil. This because the heating thermograms just for C18 in both types of oil, did not show the presence of the endotherm associated with the β polymorph. Since the development of the β phase in the C18:C14 binary mixture (0:8, 7:1, 6:2, 5:3 and 4:4 proportions) came from a polymorphic transition, the development of the β phase was not included in the C18:C14 phase diagram (Fig. 1 A). The phase diagrams were done at each MG proportion keeping a total MG concentration of 8% (wt/wt). Within this context we observed that, independent of the MG binary mixture and the type of oil, the phase transition temperature for the mixed Lα phase (T°-Lα) apparently behaved independent of the C18 molar fraction (Figs. 1 and 2 ). Nevertheless, a more in-deep analysis of the phase diagrams showed that, for the C18:C14 in the mineral oil and the C18:16 in both types of oil, the T°-Lα had a quadratic increase as a direct function of the C18 molar fraction (P < 0.05). Thus, as the concentration of the MG with the fatty acid of higher number of carbons (i.e., longer aliphatic chain) increased in the C18:C14 and the C18:16 binary mixtures, the phase transition temperature for the mixed Lα phase (i.e., the initial MGs self-assembly) showed a concave quadratic increase until achieving a maximum at a 1.0 molar fraction of C18 (Figs. 1 and 2 panels A and B). Unfortunately, the behavior of T°-Lα for the C18:C14 in the vegetable oil could not be evaluated. As previously discussed at the 7:1, 6:2, 5:3 and 4:4 C18:C14 proportions the Lα and the β phases occurred within the same temperature interval. Consequently, we could not establish a reliable phase transition for the Lα phase at molar fractions of C18 higher than 0.4 (i.e., C14 molar fractions lower than 0.6). On the other hand, independent of the type of oil, the T°-Lα in the C18:22 phase diagrams showed a small but a significant concave quadratic increase as the C22 molar fraction increased (i.e., as the concentration of the MG with the longer aliphatic chain increased) until achieving a maximum at 1.0 molar fraction of C22 (P < 0.05). We explained the T°-Lα behavior in the MG binary mixtures considering that, besides the effect of the polarity of the OH groups, the temperature for the initial MGs self-assembly depended also on the MGs’ aliphatic chains oil solubility. Thus, the higher the proportion of the MG with the longer aliphatic chain (i.e., the higher the molar fraction of C18 or C22 in the corresponding binary mixture) the lower the solubility of the mixed Lα phase in the oil and, subsequently the higher the T°-Lα (Figs. 1 and 2 ). It is important to recall that the closely packed bilayer organization of the mixed Lα phase it is a requirement for the further crystallization of the aliphatic chains in the mixed lamella (i.e., the Lα → sub-α transition). Consequently, the MGs’ composition of the Lα phase ought to determine the temperature for the sub-α phase transition. This because if the MGs’ composition of the Lα phase resulted in an efficient aliphatic chain packing, the T°-sub-α would occur at higher temperature that if the Lα phase had a less efficient aliphatic chain packing. Through experimental analysis (i.e., calorimetry and X-ray scattering) and computer simulation of tripalmitin-tristearin mixtures, Pizzirusso et al. [ 23 ] showed that the crystallization temperature followed a eutectic behavior. The crystallization behavior of the tripalmitin-tristearin mixtures was associated with the packing efficiency of the triglycerides in the mixed crystal. The authors concluded that at the eutectic point, the tripalmitin-tristearin composition in the mixed crystal resulted in less efficient chain packing and, subsequently, in a lower melting temperature. The authors associated the decrease in the melting temperature at the eutectic composition (i.e., 70% tripalmitin-30% tristearin) with a balance between enthalpic and entropic effects resulting from the packing efficiency between the triglycerides that finally determined the eutectic temperature [ 23 ]. Within this framework, we concluded that the eutectic behavior of the T° sub−α observed in both types of oils by the C18:C14, C18:16, and C18:C22 binary mixtures (Figs. 1 and 2 ), was associated with the MG composition of the mixed Lα phase and its effect in the aliphatic chain packing efficiency throughout the lamella. Thus, we considered that at the eutectic temperature for the sub-α transition (T° E sub-α), the aliphatic chains packing throughout the mixed lamella was the least efficient. This possible because at the molar composition of the mixed Lα phase, the difference in length between the aliphatic chains of the MGs resulted in the least efficient chains packing of that developed by any other MG molar fraction. Therefore, the composition of the mixed crystal at the corresponding T° E sub-α for the MG binary mixtures studied (Table 1 ), provided over all the MG proportions the lowest melting temperature for the sub-α phase. These results applied independent of the type of oil and the binary mixture of MG. We considered that the composition of the mixed crystal at T° E sub-α was closely associated with the molar MG composition of the oil solution at the corresponding eutectic point. Within this context, Table 1 includes the tentative molar MG composition of the mixed crystal at the T° E sub-α, and shows that the T° E sub-α increased in the following order: C18:C22 > C18:C16 > C18:C14 (P < 0.01; Table 1 ). These results indicated that, independent of the type of oil, the lower the aliphatic chain length of the MG that complemented with C18 the binary mixture, the lower the T° E sub-α and the higher the molar fraction of that MG that resulted in a less efficient chain packing in the mixed crystal. From the above and considering the MG oil solubility, as the temperature decreased in an oil solution of a binary MG mixture with a high C18 molar fraction, the MG driving the molecular self-assembly from the isotropic phase (i.e., isotropic phase→Lα phase) was C18. As the C18 molar fraction decreased in the binary mixture, the decrease in temperature resulted in more C14, C16 or C22 molecules integrated into the C18 lamella, resulting in less efficient MGs packing and lower Lα, and particularly, lower sub-α transition temperatures. This process occurred until at the binary MG composition associated at T° E sub-α, the least efficient MG packing was achieved (i.e., the eutectic point). Within this context, the behavior of the transition temperature for the sub-α as in the C18:C14, C18:16, and C18:C22 binary mixtures, was the result of the MGs packing as the C14, C16 or C22 molecules were integrated into the C18 lamella. This was indicated in the corresponding phase diagram by using first C18 in the nomenclature used to point out the respective MG phase, i.e., C18-C14 Lα, C18-C14 sub-α, C18-C16 Lα, C18-C16 sub-α, C18-C22 Lα, C18-C22 sub-α (Figs. 1 and 2 ). At C18 molar fractions in the binary mixture lower than the one associated with the eutectic point (Table 1 ), the MG that drove the isotropic phase→Lα and the Lα→sub-α transitions was, depending on the MG binary mixture, C14, C16, or C22. We indicated this in the corresponding phase diagrams by using first C14, C16 or C22 in the nomenclature used to point out the respective phase, i.e., C14-C18 Lα, C14-C18 sub-α, C16-C18 Lα, C16-C18 sub-α, C22-C18 Lα, C22-C18 sub-α (Figs. 1 and 2 ). Table 1 Eutectic temperature (T° E ) for the sub-α phase (T° E sub-α) and molar fraction composition for the mixed sub-α phase at T° E for each of the binary MG mixtures studied in vegetable and mineral oil. C18:C14 C18:C16 C18:C22 sub-α phase molar fraction composition at T° E T° E sub-α a (°C) sub-α phase molar fraction composition at T° E T° E sub-α a (°C) sub-α phase molar fraction composition at T° E T° E sub-α (°C) Vegetable oil 0.250 C18 0.750 C14 -1.00 b (0.01) 0.375 C18 0.625 C16 12.45 b (0.15) 0.750 C18 0.250 C22 20.64 b (0.22) Mineral oil -2.76 c (0.16) 8.58 c (0.06) 20.64 b (0.21) a Eutectic temperature for the sub-α phase reported as the mean and standard deviation (within brackets) of two independent determinations (n = 2). b, c For the same binary MG mixture a different superscript indicates a significant effect of the type of oil on the T° E sub-α (P < 0.01). 3.3 Rheological properties of the MGs and the MG binary mixtures in the vegetable and mineral oil Figure 3 shows the rheograms for the vegetable and mineral oil systems at 1.0 molar fraction of C14, C16, C18 and C22 during cooling (Figs. 3 A and 3 B) and isothermal (Figs. 3 C and 3 D) conditions. The G’ behavior during cooling was explained associating the MGs’ phase transitions through the superimposition of the cooling G’ rheograms on the corresponding cooling thermograms. The resulting graphs for some of the MGs studied (i.e., C16, C18, and C22) are shown in Figs. 4SM and 5SM (Supplementary Material). These results showed that, independent of the type of oil and the MG, the initial G’ increment observed during cooling of the MGs oil solutions was associated with the development of the isotropic phase→Lα transition (Figs. 3 A and 3 B). The G’ onset (i.e., the onset of the MGs’ self-assembly) occurred at higher temperature as the number of carbons of the aliphatic chain in the MG increased (Figs. 3 A and 3 B). This behavior was observed independent of the type of oil. As previously observed, in MG oil solutions the temperature for the onset of the molecular self-assembly increases as the number of carbons of the esterified fatty acid increased [ 8 ]. As cooling continued the crystallization of the aliphatic chains in the lamella (i.e., the Lα→sub-α1 phase transition) predominated over the Lα phase formation (i.e., the isotropic phase→ Lα phase transition). Additionally, as already discussed, in MGs with esterified fatty acids of 16 carbons and longer a sub-α2 phase transition occurs at lower temperatures than the sub-α1 phase [ 8 ]. The sub-α2 phase transition might be associated with the crystallization of a rotator phase remnant in the aliphatic chains of the MGs in the lamella [ 8 , 9 ]. Therefore, as cooling continued the crystallization heat released by the sub-α1 and sub-α2 phase transitions resulted in partial melting of the already crystallized MGs until further cooling dissipated the heat generated. The overall effect was a concomitant reduction on the G’ growth until the elasticity of the systems achieved a tentative plateau even before attaining 5°C. It is important to note that C14 does not develop the sub-α2 phase [ 7 ], and subsequently in the C14 system at 1.0 Molar fraction no additional crystallization heat was generated at temperatures below the sub-α1 phase transition. This might partially explain the G’ increase observed in the C14 system at temperatures below the sub-α1 phase transition, achieving G’ values similar to or higher than the C16 and the C18 systems (Figs. 3 A and 3 B). However, as previously discussed C14 is prone to go through a sub-α to β polymorphic transition [ 6 – 8 , 20 – 21 ]. Therefore, the development of the β polymorph during cooling might also be associated with the G’ increment observed in the C14 system at temperatures below the sub-α1 phase transition (Figs. 3 A and 3 B). The behavior of G’ under isothermal conditions (5°C) for the vegetable and mineral oil systems at 1.0 molar fraction of C14, C16, C18 and C22 is shown in Figs. 3 C and 3 D. Although G” was not included in the isothermal rheograms shown in Figs. 3 C and 3 D, the results showed that, independent of the type of oil and the MG, the G’ of the oleogels was always higher than G” during the whole isothermal period (i.e., 180 min). Although at 5°C we did not determine frequency sweeps in the 8% C14, C16, C18 and C22 oleogels, based on previous studies involving rheological measurements of vegetable oil oleogels formulated with different concentrations of C18 and a commercial MG (0.5–8% wt/wt) [ 6 ], we considered that the oleogels developed in the vegetable and mineral oil with 8% of C14, C16, C18, and C22 were true gels. Under isothermal conditions (5°C) the G’ for the MGs systems in the vegetable oil tended to achieve a plateau as a function of time, attaining higher G’ values as a direct function of the length of the aliphatic chain of the MG (Fig. 3 C). Although in the mineral oil the MGs systems also tended to achieve a G’ plateau, for the same MG system we observed different rheological behavior. Working with similar vegetable and mineral oils, Aguilar-Zárate et al. [ 24 ] reported that a commercial MG was more soluble in vegetable oil than in mineral oil. Additionally, these authors showed that after 24 h at 15°C the MG in a 2% vegetable oil solution crystallized as small acicular crystals, while in the mineral oil the MG crystallized as larger rod-shaped crystals. As previously indicated, the mineral oil was essentially composed of saturated (linear and branched) n -alkanes with a hydrocarbon chain between 15 and 50 carbons. In contrast, the vegetable oil was mainly composed by triacylglycerides (95–98%) and some additional minor components like mono-, di-acylglycerides, and free fatty acids. Then, mineral oil had lower relative polarity than vegetable oils. We consider that the relative polarity effect on the MG’s oil solubility affected the MG’s crystallization kinetics and the MG’s crystal habit. The overall result was that for the same MG we obtained a different rheological behavior in each type of oil. Thus, in the vegetable oil the G’ of the oleogels increased as a function of time achieving a plateau. López-Martínez et al. observed similar rheological behavior for vegetable oil oleogels developed with C18 at concentrations ≥ 2% [ 6 ]. These authors showed that the increase in G’ as a function of time at 5°C, could not be associated with an increase in the solid content of the oleogel since this value (measured by NMR) remained constant during the 180 min at 5°C. The authors associated the G’ behavior with an increase in the size of the plate-like shaped crystals observed in the C18 oleogels as function of time 5°C [ 6 ]. In contrast, in the mineral oil the G’ of the C16 and C18 oleogels showed a relative constant behavior during the whole isothermal period. However, under isothermal conditions the C14 oleogels showed an increase in G’ as a function of time until achieving a plateau after ≈ 165 min at 5°C (Fig. 3 D). As already indicated C14 is prone to develop a sub-α → β phase polymorphic transition [ 6 – 8 , 20 – 21 ], and our results showed that this transition occurred more evident in mineral oil than in vegetable oil (Fig. 1SM panels D and C, respectively). Therefore, the increase in G’ , particularly observed in the C14 oleogels developed in the mineral oil, might be associated with the β phase formation during cooling (Fig. 3 B) and continuing under isothermal conditions (Fig. 3 D). On the other hand, the C22 oleogels in mineral oil were the only ones that under isothermal conditions showed a pronounced curvilinear decrease until achieving a plateau after ≈ 100 min (Fig. 3 D). Unfortunately, we did not have enough C22 to determine the solid content of the oleogel as a function of time at 5°C to evaluate if the MG with the longest esterified fatty acid solubilized in the mineral oil as a function of time resulting in a G’ decrease. Nevertheless, we considered that this explanation was improbable mainly because previous studies [ 8 , 24 ] showed that C22 has lower solubility in mineral oil than in vegetable oil. Additionally, the C22 oleogels in vegetable oil did not show the decrease in G’ as a function of time at 5°C (Fig. 3 C). Evidently, we need to do additional experiments (i.e., microstructural analysis of the oleogels under cooling and isothermal conditions) to explain the rheological behavior of the MG oleogels fully. Table 2 G’ values at 5°C ( G’ 5°C ) for the oleogels developed in the vegetable or mineral oil at 1.0 molar fraction of C14, C16, C18, and C22, and for the oleogels developed with the C18:C14, C18:C16, and C18:C22 binary mixtures at the molar fraction composition associated with the eutectic point (see Table 1 ). G’ 5°C (Pa x 10 3 ) a Molar fraction of the corresponding MG C14 C16 C18 C22 C18:C14 0.250 C18 d 0.750 C14 C18:C16 0.375 C18 d 0.625 C16 C18:C22 0.750 C18 d 0.250 C22 Vegetable oil 1.0 53.16 b, e (0.47) 71.79 b, k (0.98) 86.37 b, l (1.85) 128.40 b, m (1.24) 1507.59 b, n (4.09) 369.27 b, o (3.31) 687.96 b, p (5.91) Mineral oil 1.0 67.99 c, j (0.82) 37.80 c, k (0.22) 49.14 c, l (0.10) 22.69 c, m (0.49) 595.31 c, n (1.57) 56.11 c, o (1.39) 154.04 c, p (8.11) a The G’ 5°C and corresponding standard deviation were determined from two independent determinations (n = 2) b, c For the same MG, values with different first superscript indicates a significant effect of the type of oil on the G’ 5°C of the oleogel (P < 0.01). d For the corresponding binary MG mixture this was the molar fraction composition for the mixed sub-α phase at T° E e−k For the same type of oil, G’ 5°C values with different second superscript indicates a significant effect of the MG system on the G’ 5°C of the corresponding oleogel (P < 0.01). To evaluate the type of oil effect on the elastic properties of the C14, C16, C18, and C22 oleogels, we determined, in each of the two independent isothermal rheograms an average G’ using the measurements from the last 5 min at 5°C. With these values we then calculated, for each of the MG oleogels, a mean G’ ( G’ 5°C ) and associated standard deviation (Table 2 ). The corresponding statistical analysis showed that, except the C14 oleogels, the G’ 5°C of the C16, C18, and C22 oleogels in vegetable oil was significantly higher than the G’ 5°C of the corresponding MG oleogel in the mineral oil (P < 0.01). Given the rheological behavior observed by the C22 oleogels in the mineral oil (Fig. 3 D), the G’ 5°C for the C22 oleogels in vegetable oil was particularly higher than the one obtained by the C22 oleogels in the mineral oil (Table 2 ), this. On the other hand, the G’ 5°C of the C14 oleogels developed in the mineral oil was higher than the G’ 5°C of the C14 oleogels formulated with vegetable oil (P < 0.01), tentatively because in the mineral oil oleogels the C14 developed higher amounts of the β phase. The overall result was that, in the vegetable oil the C22 oleogels achieved the highest G’ 5°C and the C14 oleogels the lowest G’ 5°C while the opposite occurred with the corresponding mineral oil oleogels (Table 2 ). Finally, using vegetable and mineral oil solutions with MG proportions selected from the ones used in the C18:C14, C18:C16, and C18:C22 phase diagrams (Figs. 1 and 2 ), we determined their rheological behavior using the same time-temperature conditions as with the C14, C16, C18 and C22 systems. This to evaluate the effect of the MG binary mixture composition on the rheological properties of the vegetable and mineral oil oleogels. It is important to note that these oleogels were done with the same total MG concentration (i.e., 8% wt/wt) as in the MG oil solutions used to determine the phase diagrams. The selected MG proportions from each MG binary mixture, included the one associated with the eutectic point (Table 1 ) and MG proportions above and below the corresponding eutectic point. Within this context, Figs. 4 to 11 show the rheological profiles obtained at different MG proportions of the C18:C16 and C18:C22 systems in vegetable and mineral oil. Overall, the binary MG mixtures in each type of oil, including the 18:14 system (results not shown), showed similar rheological behavior during cooling (Figs. 4 , 6 , 8 , and 10 ) as the one observed by the C14, C16, C18 and C22 systems (Fig. 3 ). However, the binary MG mixtures showed one major difference in their rheological behavior with respect to the one observed by the C14, C16, C18 and C22 systems. This because after the G’ onset associated with the development of the Lα phase, the G’ showed a plateau followed by a second steady G’ increment and then by a second G’ plateau. This rheological behavior was observed in all the binary MG mixtures independent of the type of oil (Figs. 4 , 6 , 8 , and 10 ). Always, the second G’ growth occurred below the temperature for the sub-α phase transition (temperature indicated with an arrow in Figs. 4 , 6 , 8 , and 10 ). It is important to recall that, in contrast with the 1.0 molar oil solutions of C16, C18, and C22, the cooling and heating thermograms of the binary MG mixtures in vegetable or mineral oil did not develop the sub-α2 phase (Figs. 1SM to 3SM). It seemed that the mixed aliphatic chains packing hindered the crystallization of the rotator phase tentatively associated with the sub-α2 transition [ 6 , 8 ]. Consequently, in contrast with the G’ profile of the C16, C18, and C22 systems during cooling (Figs. 3 A and 3 B), the crystallization heat associated with the sub-α2 transition did not affect the rheological behavior of the MG binary mixtures. The corresponding G’ behavior under isothermal conditions of the C18:C16 and C18:22 oleogels in vegetable and mineral oil are shown in Figs. 5 , 7 , 9 and 11 . As stated previously, we did not determine frequency sweeps of the oleogels to establish if the systems could be considered true gels. However, based on previous rheological studies done with vegetable oil oleogels developed with different concentrations (0.5–8% wt/wt) of a commercial mixture of C16 and C18 [ 6 ], we considered that the oleogels developed by the binary MG mixtures were true gels. Additionally, as with the C14, C16, C18, and C22 oleogels, independent of the type of oil, the G’ of the C18:C16 and C18:22 oleogels were always higher than G” during the whole isothermal period (i.e., 180 min). Similar rheological behavior was observed by the C18:C14 oleogels (data not shown). Furthermore, independent of the type of oil, during the whole isothermal period most of the oleogels developed by the binary MG mixtures showed a relative constant G’ . Just the C18:C16 oleogel developed with a C18 molar fraction of 0.375 (Fig. 5 B), the C18:C22 oleogel developed with a C18 molar fraction of 0.75 (Fig. 9 B) both in vegetable oil, and the C18:C16 mineral oil oleogel developed with a C18 molar fraction of 0.125 (Fig. 7 D) showed a G’ increment until achieving a plateau after 140–160 min at 5°C. We considered that this G’ increment was associated with changes in the microstructural arrangement of the MG crystals rather than with additional MG crystallization occurring under isothermal conditions. It is important to make additional studies to explain this behavior, mainly because most of the oleogels showing this rheological behavior corresponded to those formulated with the MG composition associated with the eutectic point. After calculating the G’ 5°C from the corresponding isothermal rheogram, it was evident that, except the 18:16 oleogels in mineral oil, independent of the type of oil, the oleogels that achieved the highest elasticity were those formulated with the molar fraction composition associated with the eutectic point (P < 0.01; Table 1 SM). The 18:16 oleogels in mineral oil formulated with 0.125 of C18 and 0.875 of C16 was the only system that achieved higher G’ 5°C than the G’ 5°C of the oleogel with MG composition associated with the eutectic point (Table 1 and Fig. 2 B). However, the difference between the G’ 5°C of this oleogel and the one of the oleogel formulated with MG composition associated with the eutectic point was not as large as the one observed by the same oleogels in vegetable oil (Table 1 SM). In any case, the oleogels formulated with the molar fraction composition of the eutectic point achieved higher G’ 5°C than the oleogels formulated at 1.0 molar fraction of C16, C18, and C22 (P < 0.01; Table 1 SM), and effect that was more evident with the vegetable oil oleogels (Table 1 SM). As previously discussed, for each of the binary mixtures the corresponding MG composition at the eutectic point developed the least efficient aliphatic chains packing in the sub-α phase. We considered that the microstructure developed by the aliphatic chain packing at the eutectic point favored the incorporation and retention of higher amounts of oil resulting in oleogels with higher elasticity. This in contrast with the elasticity achieved by the oleogels developed just by the individual MG and with binary MG composition different from the one associated with the eutectic point. Again, this except the G’ 5°C achieved by the C18:C16 oleogel in mineral oil formulated with 0.125 of C18 and 0.875 of C16. The higher G’ 5°C achieved by the vegetable oil oleogels in contrast with the mineral oil oleogels, had to be associated with the relative polarity effect on the MG crystal habit, particularly in the MG’s crystal size and shape. As already mentioned, in vegetable oil the MG crystallizes as small acicular crystals, while in the mineral oil the MG crystallizes as larger rod-shaped crystals [ 24 ]. Thus, the crystal network microstructure developed by small crystals ought to provide a larger solid surface to liquid phase ratio than the microstructure developed by larger crystals. This could explain the higher G’ 5°C achieved by the vegetable oleogels in comparison with the one achieved by the mineral oil oleogels. To explain the differential effect of the vegetable and the mineral oil on the rheological properties of oleogels developed by binary MG mixtures, we need to do microstructural and thermo-mechanical analysis, and also solid content and X ray measurements during oleogelation (i.e., cooling and isothermal conditions). 4. CONCLUSIONS To our knowledge this is the first report that establishes the eutectic behavior of the sub-α phase in binary mixtures of saturated MG, and its relationship with the rheological properties of the MG oleogels. The phase diagrams obtained for the C18:C14, C18:16, and C18:C22 binary mixtures in the vegetable and mineral oil, showed that the eutectic behavior of the T° sub-α was closely associated with the MG composition of the mixed Lα phase and with the aliphatic chains packing efficiency of the sub-α phase. We considered that at the MG molar composition corresponding to the eutectic point, the difference in length between the aliphatic chains in the mixed lamella resulted in a sub-α phase with the least efficient chain packing of that developed by any other MG molar fraction. It seemed that the aliphatic chain packing developed at the eutectic point by the binary mixtures of MG favored the incorporation and retention of higher amounts of oil, resulting in oleogels with higher elasticity. This in contrast with the elasticity achieved by the oleogels developed just by the individual MG and with binary MG composition different from the one associated with the eutectic point. However, although for each of the binary mixtures the corresponding MG composition at the eutectic point was the same in both oils (Table 1 ), the oleogels developed in the vegetable oil achieved higher elasticity than the mineral oil oleogels. Evidently, there is an effect of the type of oil (i.e., solvent relative polarity) on the rheological properties of the oleogels developed by binary MG mixtures, particularly with the MG composition associated with the eutectic point. We need to do additional studies involving microstructural and thermo-mechanical analysis, solid content and X ray measurements during the development of oleogels by binary MG mixtures using solvents of different polarity. This is particularly relevant for the cosmetic industry, where binary mixtures of MG could be used in the development of oleogels formulated using medium-chain triglycerides alone or in combination with other organic solvents of higher polarity like glycerol, 1,3-butanediol, 1,3-propanediol, 1, 6-hexanediol, 2-butoxyethanol or ester like 1-Methoxy-2-propanol acetate. Declarations CONFLICT OF INTEREST The authors declare that they have no conflict of interest. Author Contribution M. E., Charó-Alvarado is currently a Ph. D. student, and these results are part of her thesis research. She was closely involved in the DSC and rheology measurements. M. A. Charó-Alonso was involved in data collection and along with M. E., Charó-Alvarado established the experimental conditions. J. F. Toro-Vazquez conception and design of the study, project and research group leader, also acting as M. E., Charó Alvarado's thesis advisor. The first draft of the manuscript was written by J. F. Toro-Vazquez and all authors contributed and commented on further versions of the manuscript. All authors read and approved the final manuscript. Acknowledgments The present research was supported by Consejo Nacional de Ciencia y Tecnología (CONACYT) through the grant CB-280981-2018. M. E., Charó Alvarado greatly appreciates the scholarship provided by CONACYT to conclude her Ph.D. program. References M.E. Morales, V. Gallardo, B. Clarés, M.B. García, M.A. Ruiz, Int. J. Cosmet. Sci. 60 (6), 627 (2009) D.S. Morrison, J. Schmidt, R. Paulli, J. Appl. Cosmetol. 14, 111 (1996) Z. Wang, J. Chandrapala, T. Truong, A. Farahnaky, Food Sci. Nutr. 63(23), 6069 (2023) F. C. S. César, P. M. B. G. Maia Campos, Int. J. Cosmet. Sci. 42, 494 (2020) J. F. Toro-Vazquez, J. A. Morales-Rueda, A. Torres-Martínez, M. A. Charó-Alonso, V. A. Mallia, R. G. Weiss, Lagmuir 29(25), 7642 (2013) A. López-Martínez., J.A. Morales-Rueda, E. Dibildox-Alvarado, M.A. Charó-Alonso, A.G. Marangoni, J.F. Toro-Vazquez, Food Res. Int. 64, 946 (2014) E. S. Lutton, J. of the Am. Oil Chem. Soc. 48(12), 778 (1971) M. Charó-Alvarado, M. Charo, A. De la Peña Gil, J. Toro-Vazquez, Food Biophys. 18(4), 1 (2023). A. López-Martínez, M.A. Charó-Alonso, A. G. Marangoni, J.F. Toro-Vazquez, Food Res. Int. 72, 37 (2015) D. Cholakova, N. Denkov, (2019). Adv. in colloid and intf. Sci. 269, 7 (2019) D. Cholakova, K. Tsvetkova, S. Tcholakova, N. Denkov, Colloids Surf. A Physicochem. Eng. Asp. 634, 127926 (2022) J. F. Toro-Vazquez, J. D. Pérez-Martínez in Molecular Gels: Structure and Dynamics, ed. by R.G. Weiss (The Royal Society of Chemistry, 2018), pp. 57–87 S. Hasnain, Energy Conv. Mgmt. 39, 1139 (1998) K. Huizhen, Appl. Therm. Engg. 113, 1319 (2017) P. Zhao, Q. Yue, H. He, B. Gao, Y. Wang, Q. Li, Appl. Energy 115, 483 (2014) U. Gala, H. Pham, H. Chauman, J. Develop. Drugs 2(3), 130 (2013) I. Balakrishnan, N. Jawahar, V. Senthil, D. Debosmita, Int. J. Res. Pharm. Sci. 11(3), 3017 (2020) J. Tang, R. Daiyan, M.B. Ghasemian, Nat. Commun. 10, 4645 (2019) T. Malkin, M.R.J. Shurbagy. J. Chem. Soc. 0, 1628 (1936) C. H. Chen, E. M. Terentjev, in Edible Oleogels: Structure and Health Implications, ed. by A.G. Marangoni, N. Garti (Elsevier, 2011), pp. 173–201 C. H. Chen, I. Van Damme, E. M. Terentjev, Soft Matter 5(2), 432 (2009) C. H. Chen, E. M. Terentjev, Langmuir 25(12), 6717 (2009) A, Pizzirusso, F. Peyronel, E. D. Co, A. G. Marangoni, G. Milano, J. of the Am. Oil Chem. Soc, 140(39), 12405 (2018) M. Aguilar-Zárate, A. De la Peña-Gil, F.M. Álvarez-Mitre, M.A. Charó-Alonso, J.F. Toro-Vazquez. Food Biohys. 14, 326 (2019) Additional Declarations No competing interests reported. Supplementary Files SUPPLEMENTARYINFORMATION.pdf Cite Share Download PDF Status: Under Review Version 1 posted Reviews received at journal 05 Mar, 2024 Reviewers agreed at journal 07 Feb, 2024 Reviewers agreed at journal 05 Feb, 2024 Reviewers invited by journal 05 Feb, 2024 Submission checks completed at journal 04 Feb, 2024 Editor assigned by journal 04 Feb, 2024 First submitted to journal 04 Feb, 2024 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-3928380","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":271152155,"identity":"4af8fae5-3f26-4a8a-9552-dc75a3a53e30","order_by":0,"name":"Maria E. Charó-Alvarado","email":"","orcid":"","institution":"Universidad Autónoma de San Luis Potosí","correspondingAuthor":false,"prefix":"","firstName":"Maria","middleName":"E.","lastName":"Charó-Alvarado","suffix":""},{"id":271152156,"identity":"5c280bb9-53e4-48ad-be15-7b65d660e377","order_by":1,"name":"Miriam A. Charó-Alonso","email":"","orcid":"","institution":"Universidad Autónoma de San Luis Potosí","correspondingAuthor":false,"prefix":"","firstName":"Miriam","middleName":"A.","lastName":"Charó-Alonso","suffix":""},{"id":271152157,"identity":"bedf2ae9-e08d-4661-9b73-d68e325b51ac","order_by":2,"name":"J. F. Toro-Vazquez","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAm0lEQVRIiWNgGAWjYLCCD0DMR7RqHiBmnAEk2EjSwsxDkhZ79t6Hj23b7OzZpBtYN/MQZQvPcWPj3LbkxDaZA2w3ZxClRSKNTTq3jTmBTSKB7cYHorVYttXbg7UkEK2Fse0wYxvxtpw5xmzYc+440C8H24jzC3t7G+ODH2XV9vzSzcduExViCCDB2ECaBqAWUjWMglEwCkbBiAEAWH0opSCOv+4AAAAASUVORK5CYII=","orcid":"","institution":"Universidad Autónoma de San Luis Potosí","correspondingAuthor":true,"prefix":"","firstName":"J.","middleName":"F.","lastName":"Toro-Vazquez","suffix":""}],"badges":[],"createdAt":"2024-02-04 17:59:15","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-3928380/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-3928380/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":50726473,"identity":"ba24f5e1-b056-4822-ad9e-556a02a5ae09","added_by":"auto","created_at":"2024-02-06 11:30:49","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":49538,"visible":true,"origin":"","legend":"\u003cp\u003ePhase diagrams for the C18:C14 (A), C18:C16 (B), and C18:C22 (C) binary mixtures in vegetable oil. The phase diagrams are shown as a function of the molar fraction of the monoglycerides involved in the binary mixtures. The dotted line indicates the molar fraction composition of the mixed MG crystal at the eutectic point. The monoglyceride that mainly drove the phase transition (i.e., Lα and sub-α) above or below the eutectic point, is written first in the nomenclature used to indicate the corresponding phase.\u003c/p\u003e","description":"","filename":"FIG1.png","url":"https://assets-eu.researchsquare.com/files/rs-3928380/v1/005caefbc6e10b034acbd40a.png"},{"id":50726470,"identity":"732504d0-e375-417d-bfe7-bcd90b10a5d5","added_by":"auto","created_at":"2024-02-06 11:30:49","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":50753,"visible":true,"origin":"","legend":"\u003cp\u003ePhase diagrams for the C18:C14 (A), C18:C16 (B), and C18:C22 (C) binary mixtures in mineral oil. The phase diagrams are shown as a function of the molar fraction of the monoglycerides involved in the binary mixtures. The dotted line indicates the molar fraction composition of the mixed MG crystal at the eutectic point. The monoglyceride that mainly drove the phase transition (i.e., Lα and sub-α) above or below the eutectic point, is written first in the nomenclature used to indicate the corresponding phase\u003c/p\u003e","description":"","filename":"FIG2.png","url":"https://assets-eu.researchsquare.com/files/rs-3928380/v1/0bf5ef2d9a959f4d91122b8d.png"},{"id":50726471,"identity":"62d19b68-096b-4eb2-a243-9d50e8ee384e","added_by":"auto","created_at":"2024-02-06 11:30:49","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":35618,"visible":true,"origin":"","legend":"\u003cp\u003eEvolution of the elastic (\u003cem\u003eG’\u003c/em\u003e) modulus during cooling (80°C to 5°C, 10 °C/min; panels A and B) and during isothermal conditions (5°C; panels C and D) for the 8% vegetal (panels A and C) and mineral (panels B and D) oil solutions of the monoglycerides studied. The 8% MG oil solution corresponded to the 1.0 molar fraction for C14, C16, C18, and C22. The arrows indicate the temperature for the sub-α phase transition.\u003c/p\u003e","description":"","filename":"FIG3.png","url":"https://assets-eu.researchsquare.com/files/rs-3928380/v1/af5afc7773b8dabde26c1362.png"},{"id":50726879,"identity":"2378a70d-ebb5-4908-a3ae-43fe89ec4c33","added_by":"auto","created_at":"2024-02-06 11:38:49","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":32318,"visible":true,"origin":"","legend":"\u003cp\u003eEvolution of the elastic modulus (\u003cem\u003eG’\u003c/em\u003e) during cooling (80°C to 5°C, 10 °C/min) for the C18:C16 binary mixture in vegetal oil at different C18 molar fractions: 0.875 (A), 0.50 (B), 0.375 (C), and 0.125 (D). Panel C includes the rheogram at the C18:C16 molar fraction composition corresponding to the eutectic point (see Fig. 1 and Table 1). The arrow indicates the temperature where the sub-α phase transition occurred in the corresponding C18:C16 binary mixture.\u003c/p\u003e","description":"","filename":"Fig4.png","url":"https://assets-eu.researchsquare.com/files/rs-3928380/v1/35c3af3a789aa6e5d8ed1fcc.png"},{"id":50726883,"identity":"9cbf361e-e3d3-4fe0-aa05-996ccbc8f693","added_by":"auto","created_at":"2024-02-06 11:38:50","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":21292,"visible":true,"origin":"","legend":"\u003cp\u003eEvolution of the elastic modulus (\u003cem\u003eG’\u003c/em\u003e) at 5°C for the C18:C16 binary mixture in vegetable oil at different C18 molar fractions: 0.875 (A), 0.50 (B), 0.375 (C), and 0.125 (D). Panel C includes the rheogram at the C18:C16 molar fraction composition corresponding to the eutectic point (see Fig. 1 and Table 1).\u003c/p\u003e","description":"","filename":"Fig5.png","url":"https://assets-eu.researchsquare.com/files/rs-3928380/v1/9f048ed5dcd0fedca148d68c.png"},{"id":50726880,"identity":"f36fe4fc-1891-4236-bcfb-a55422b0a850","added_by":"auto","created_at":"2024-02-06 11:38:49","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":33094,"visible":true,"origin":"","legend":"\u003cp\u003eEvolution of the elastic modulus (\u003cem\u003eG’\u003c/em\u003e) during cooling (80°C to 5°C, 10 °C/min) for the C18:C16 binary mixture in mineral oil at different C18 molar fractions: 0.875 (A), 0.50 (B), 0.375 (C), and 0.125 (D). Panel C includes the rheogram at the C18:C16 molar fraction composition corresponding to the eutectic point (see Fig. 1 and Table 1). The arrow indicates the temperature where the sub-α phase transition occurred in the corresponding C18:C16 binary mixture.\u003c/p\u003e","description":"","filename":"Fig6.png","url":"https://assets-eu.researchsquare.com/files/rs-3928380/v1/a61076ad4f3967899e4c639c.png"},{"id":50726475,"identity":"c2eab939-ad1d-4232-95bd-8611b432a7bb","added_by":"auto","created_at":"2024-02-06 11:30:49","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":22790,"visible":true,"origin":"","legend":"\u003cp\u003eEvolution of the elastic modulus (\u003cem\u003eG’\u003c/em\u003e) at 5°C for the C18:C16 binary mixture in mineral oil at different C18 molar fractions: 0.875 (A), 0.50 (B), 0.375 (C), and 0.125 (D). Panel C includes the rheogram at the C18:C16 molar fraction composition corresponding to the eutectic point (see Fig. 1 and Table 1).\u003c/p\u003e","description":"","filename":"Fig7.png","url":"https://assets-eu.researchsquare.com/files/rs-3928380/v1/69bf490031329c1004e904ba.png"},{"id":50726882,"identity":"0c5bc448-464a-4fb9-96a2-c75531b57f56","added_by":"auto","created_at":"2024-02-06 11:38:49","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":33697,"visible":true,"origin":"","legend":"\u003cp\u003eEvolution of the elastic modulus (\u003cem\u003eG’\u003c/em\u003e) during cooling (80°C to 5°C, 10 °C/min) for the C18:C22 binary mixture in vegetal oil at different C18 molar fractions: 0.875 (A), 0.75 (B), 0.50 (C), and 0.125 (D). Panel B includes the rheogram at the C18:C22 molar fraction composition corresponding to the eutectic point (see Fig. 1 and Table 1). The arrow indicates the temperature where the sub-α phase transition occurred in the corresponding C18:C22 binary mixture.\u003c/p\u003e","description":"","filename":"Fig8.png","url":"https://assets-eu.researchsquare.com/files/rs-3928380/v1/d34912e3b733ce46ff557197.png"},{"id":50726480,"identity":"f9452f76-0d80-437e-b111-3563598b8dd4","added_by":"auto","created_at":"2024-02-06 11:30:49","extension":"png","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":20887,"visible":true,"origin":"","legend":"\u003cp\u003eEvolution of the elastic modulus (\u003cem\u003eG’\u003c/em\u003e) at 5°C for the C18:C22 binary mixture in vegetal oil at different C18 molar fractions: 0.875 (A), 0.75 (B), 0.50 (C), and 0.125 (D). Panel B includes the rheogram at the C18:C22 molar fraction composition corresponding to the eutectic point (see Fig. 1 and Table 1).\u003c/p\u003e","description":"","filename":"Fig9.png","url":"https://assets-eu.researchsquare.com/files/rs-3928380/v1/4c32d9bf10ac830c2a872265.png"},{"id":50727428,"identity":"8b02f07a-bc38-4103-80b8-4abcb507004d","added_by":"auto","created_at":"2024-02-06 11:46:49","extension":"png","order_by":10,"title":"Figure 10","display":"","copyAsset":false,"role":"figure","size":32379,"visible":true,"origin":"","legend":"\u003cp\u003eEvolution of the elastic modulus (\u003cem\u003eG’\u003c/em\u003e) during cooling (80°C to 5°C, 10 °C/min) for the C18:C22 binary mixture in mineral oil at different C18 molar fractions: 0.875 (A), 0.750 (B), 0.50 (C), and 0.125 (D). Panel B includes the rheogram at the C18:C22 molar fraction composition corresponding to the eutectic point (see Fig. 1 and Table 1). The arrow indicates the temperature where the sub-α phase transition occurred in the corresponding C18:C16 binary mixture.\u003c/p\u003e","description":"","filename":"Fig10.png","url":"https://assets-eu.researchsquare.com/files/rs-3928380/v1/3c24f0c152d1882a1a6e2666.png"},{"id":50726477,"identity":"f742ee8e-742f-4ecc-8ee3-f8aff951417f","added_by":"auto","created_at":"2024-02-06 11:30:49","extension":"png","order_by":11,"title":"Figure 11","display":"","copyAsset":false,"role":"figure","size":22895,"visible":true,"origin":"","legend":"\u003cp\u003eEvolution of the elastic modulus (\u003cem\u003eG’\u003c/em\u003e) at 5°C for the C18:C22 binary mixture in mineral oil at different C18 molar fractions: 0.875 (A), 0.75 (B), 0.50 (C), and 0.125 (D). Panel B includes the rheogram at the C18:C22 molar fraction composition corresponding to the eutectic point (see Fig. 1 and Table 1).\u003c/p\u003e","description":"","filename":"Fig11.png","url":"https://assets-eu.researchsquare.com/files/rs-3928380/v1/7bfd8f53821e7869e2a61730.png"},{"id":50727846,"identity":"004c3397-1e15-4078-8867-1c9ceacb775a","added_by":"auto","created_at":"2024-02-06 11:54:50","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":589961,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-3928380/v1/af423bde-d8bd-456b-b702-b7b6a16b130c.pdf"},{"id":50726481,"identity":"99cbacc8-1f62-42ec-8356-78f3fd0960bd","added_by":"auto","created_at":"2024-02-06 11:30:49","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":321073,"visible":true,"origin":"","legend":"","description":"","filename":"SUPPLEMENTARYINFORMATION.pdf","url":"https://assets-eu.researchsquare.com/files/rs-3928380/v1/0ee38f684f1c2bc28a3f9790.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003ePhase Diagrams of Binary Mixtures of Saturated Monoglycerides in Vegetable and Mineral Oil and Their Impact in the Oleogels Rheology\u003c/p\u003e","fulltext":[{"header":"1. INTRODUCTION","content":"\u003cp\u003eMolecular gels, also known as organogels or oleogels (i.e., organogels when the liquid phase is vegetable or mineral oil) is a particular class of gel composed of an organic solvent physically trapped within a supramolecular structure developed through the spontaneous self-assembly of low molecular weight (\u0026lt;\u0026thinsp;3000 Da) molecules (i.e., gelator molecules). The molecular self-assembly usually occurs at temperatures below the gelator\u0026rsquo;s solubility limit in the solvent (i.e., the vegetable or mineral oil). The potential use of oleogels developed with edible oils resides in their use as replacement of the solid phase provided by saturated and \u003cem\u003etrans\u003c/em\u003e fats to different food systems (i.e., margarines, confectionery, and table spreads, shortennings). On the other hand, we can also develop oleogels with useful and novel functional properties for the cosmetics industry [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e], where mineral oil is a solvent commonly used in the formulation of these products [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. In any case, the rheological properties of the oleogels are of utmost importance in determining relevant functional properties of food products and cosmetics like texture and oil binding capacity [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eThe molecular self-assembly that upon cooling follows common lipophilic gelator (i.e., \u003cem\u003en\u003c/em\u003e alkanes, fatty acids, long chain esters, 12-hydroxysteaic acid) in vegetable or mineral oil solutions for the development of oleogels shows just one major sol \u0026rarr; gel transition. In contrast, the organogelation of amphipathic molecules like phospholipids (i.e., lecithin) and monoglycerides (MGs) in oil solution show the development of several mesophase structures derived from the polar and the hydrophobic character of their chemical structure and functional groups (i.e., OH and phosphate groups, alkyl chains). The interactions of these functional groups with the oil determine the gelator-gelator and the gelator-solvent interactions, and subsequently whether the gelator would be soluble (i.e., no gelation), not soluble (i.e., the gelator precipitates) in the oil, or able of developing a supramolecular structure that physically traps the oil forming a self-supporting structure [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. In the case of the monoglycerides (MGs), upon cooling MGs oil solutions at low concentration (i.e., \u0026lt; 1%) from the isotropic phase, the monoglycerides develop micelles with an inverse organization. In contrast, at concentrations above the critical micelle concentration the MGs directly develop inverse lamellar bilayer structures (i.e., the Lα mesophase). In the inverse Lα phase the polar \u0026ldquo;head\u0026rdquo; groups are closely packed in a bilayer organization with the aliphatic \u0026ldquo;tails\u0026rdquo; pointing toward the oil phase. Upon further cooling, the aliphatic chains of the MGs crystallize developing the sub-α phase. Our initial studies with vegetable oil solutions of a neat MG (i.e., 1-mono-stearyloyl-glycerol) and a commercial MG (i.e., a mixture of 1-mono-stearyloyl-glycerol and 1-mono-palmitoyl-glycerol) showed the Lα and the sub-α phases form the microstructure that provides the thermo-mechanical properties of MG oleogels [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. Additionally, the initial studies of Lutton showed that only in MGs with esterified fatty acids longer than 16 carbons an additional transition occurs at lower temperatures than the Lα \u0026rarr; sub-α transition (i.e., the sub-α2 phase) [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. However, a recent study showed that the sub-α2 phase can also be developed by MGs with esterified fatty acids of 16 carbons [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. The sub-α1 \u0026rarr; sub-α2 transition might to be associated with the crystallization of a rotator phase remnant after the initial crystallization of the aliphatic chains in the Lα phase of the MGs [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. The flow properties of various phase-change materials used in energy storage, the formation of superhydrophobic and self-healing cuticle layers in plants and insects, and the rheological and textural properties of foods and cosmetic products have been associated with the temperature interval where the crystallization\u0026harr;melting of rotator phases occurs [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Then upon applying cooling-heating cycles to neat samples or vegetable and mineral oil solutions of MGs with esterified fatty acids of 16 carbons or longer, the order of the reversible phase transitions is Lα ⇄ sub-α1 ⇄ sub-α2. Within this context, the phase diagrams are used to describe the phases occurring and coexisting during molecular self-assembly and subsequent crystallization of pure gelators, gelator solutions or organogels (i.e., MGs oleogels). This, as a function of temperature and gelator concentration, assuming sufficient time and energy to achieve thermodynamic equilibrium conditions are provided [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. To evaluate the practical use of MG oleogels is important to establish the relationship between the MGs\u0026rsquo; phase diagrams in vegetable and mineral oils and the corresponding oleogel\u0026rsquo;s rheological properties. This since the viscoelastic properties of the MG oleogels are essential in the production of \u003cem\u003etrans\u003c/em\u003e-free substitutes for food systems and the manufacture of cosmetics with useful and novel functional properties. In the food and cosmetic industry saturated monoglycerides are commonly used at high purity (i.e., \u0026ge; 90%) as distilled MGs or as a mixture of MGs where C18 is usually one component.\u003c/p\u003e \u003cp\u003eWithin the previous framework the present study established the phase diagrams of mixtures of \u003cem\u003erac\u003c/em\u003e-1-stearoyl glycerol (C18) with different proportions of \u003cem\u003erac\u003c/em\u003e-1-myristoyl glycerol (C14), \u003cem\u003erac\u003c/em\u003e-1-palmitoyl glycerol (C16) or 1-monobehenin glycerol (C22) in vegetable and mineral oil. The phase diagrams of the MGs mixtures were elaborated at different molar fractions keeping the total concentration of MGs at 8% (wt/wt). Acknowledgment of the phase diagrams of amphipathic gelator molecules (i.e. pure MG solutions and MGs mixture solutions) are a major step in developing any industrial application. Additionally, at some molar fractions used in the elaboration of the phase diagrams, specifically including the MGs mixture where we observed the eutectic temperature, we evaluated the evolution of the rheology during the development of the MGs oleogel (i.e., cooling from 80\u0026deg;C to 5\u0026deg;C) and of the MGs oleogel under isothermal conditions (i.e., 3 h at 5\u0026deg;C). A eutectic system is a mixture of at least two components (i.e., two MGs) that has a melting temperature lower than any of the constitutive compounds. [\u003cspan additionalcitationids=\"CR14\" citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. There is no information regarding the rheological behavior of oleogels developed with eutectic mixtures of MG. This information would be relevant for the industrial application of MG oleogels, mainly because eutectic mixtures usually crystallize as one common crystal developing systems with physical properties that cannot be obtained with other non-eutectic mixtures (i.e., enhanced rheological properties, no phase separation, smaller crystal size distribution) [\u003cspan additionalcitationids=\"CR17\" citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e].\u003c/p\u003e"},{"header":"2. MATERIALS AND METHODS","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003e2.1. Materials\u003c/h2\u003e \u003cp\u003eThe vegetable oil used was a refined, bleached, and deodorized high oleic safflower oil obtained from a local distributor (Coral Internacional, San Luis Potos\u0026iacute;, M\u0026eacute;xico). Its detailed composition of triacylglyceride (TAGS) was previously reported [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e], showing that the major TAGS were OOO (65.65% \u0026plusmn; 0.15%), LOO (16.26% \u0026plusmn; 0.04), and POO (8.58% \u0026plusmn; 0.04) (O\u0026thinsp;=\u0026thinsp;oleic acid; L\u0026thinsp;=\u0026thinsp;linoleic acid; P\u0026thinsp;=\u0026thinsp;palmitic acid). The mineral oil was constituted, according to the manufacturer (Hycel de M\u0026eacute;xico, Jal., M\u0026eacute;xico), by a mixture of long chain alkanes. The \u003cem\u003erac\u003c/em\u003e-1-myristoyl glycerol (C14), \u003cem\u003erac\u003c/em\u003e-1-palmitoyl glycerol (C16), and \u003cem\u003erac\u003c/em\u003e-1-stearoyl glycerol (C18) were obtained from Sigma-Aldrich (St. Louis, MO), and the 1-monobehenin glycerol (C22) from INDOFINE Chemical Company Inc. (Hillsborough, NJ). According to the manufacturers the MGs had a purity above 99%.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003e2.2. Differential scanning calorimetry analysis of the mixtures of MGs in the VO and MO\u003c/h2\u003e \u003cp\u003eIn 12 x 35 mm glass vials we prepared vegetable and mineral oil solutions of MGs mixtures (i.e., C18:C14, C18:16, and C18:C22) always keeping a total MG concentration of 8% (wt/wt). The proportions of C18 to C14, C16 or C22 in each type of oil were 8:0, 7:1, 6:2, 5:3, 4:4, 3:5, 2:6.1:7, and 0:8 (wt%:wt%), corresponded to molar fractions of C18 in each MG mixture of 1.0, 0.875, 0.75, 0.625, 0.50, 0.375, 0.25, 0.125, and 0.0, respectively. Likewise, the C18 to C14, C16 or C22 proportions studied corresponded to molar fractions of C14, C16 or C22 in each MG mixture of 0.0, 0.125, 0.25, 0.375, 0.50 0.625, 0.75, 0.875, and 1.0. To achieve full solubility of the MGs the C18:C14 and C18:16 dispersions were heated at 85\u0026deg;C for 20 min, and the C18:C22 to 95\u0026deg;C for 20 min with intermittent gently stirring. Then, the vials with the MG mixtures oil solution were allowed to cool at room temperature (\u0026asymp;\u0026thinsp;20\u0026deg;C) and subsequently stored at 5\u0026deg;C. Samples (\u0026asymp;\u0026thinsp;10\u0026ndash;15 mg) of the VO and MO solutions of the MG mixtures were sealed in Tzero aluminum pans (of a maximum volume of 20 \u0026micro;L), heated at 90\u0026deg;C for 20 min and then cooled to -20\u0026deg;C at 10\u0026deg;C/min in a DSC (Q2000, TA Instruments; New Castle, DL). After 2 min at this temperature the system was heated at 5\u0026deg;C/min until reached 85\u0026deg;C. Using the first derivative of the heat flow as a function of temperature obtained with the equipment software (Universal Analysis 2000 v 4.5 built 4.5.0.5, TA Instruments; New Castle, DL), we determined the crystallization temperature (T\u003csub\u003eCr\u003c/sub\u003e) at the minimum heat flow of the different phase transitions observed in the cooling thermograms. In the same way, we determined the melting temperature (T\u003csub\u003eM\u003c/sub\u003e) at the maximum heat flow of the endotherms associated with the phase transitions observed in the heating thermograms. The phase diagrams for each MG mixture in the VO and MO solution were established based on the crystallization and melting thermograms, and on the phase diagrams for the pure MG oil solutions previously recently published [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003e2.3. Rheology measurements of the MG mixtures\u003c/h2\u003e \u003cp\u003eAt particular molar fractions of C18 in the mixture with C14, C16, and C22 (i.e., 1.0, 0.875, 0.50, 0.125, 0.0 and the corresponding molar fraction at the eutectic point of the C18:C14, C18:16, and C18:C22 mixture), we evaluated the rheological properties of the MG mixtures in the oil using a Discovery HR3 rheometer (TA-Instruments; New Castle, DL, USA) equipped with a sand-blasted parallel plate-plate geometry (model 105670, 25 mm diameter) and a true-gap system. The temperature was controlled with a Peltier system located on the base of the geometry additionally supported with a ThermoCube Liquid-Liquid recirculating chiller system (Solid state cooling system; Wappingers Falls, NY, USA). The rheometer was controlled through the equipment software (Trios V 3.0.0.3156, TA Instruments-Waters LLC, New Castle, D. E.). A sample of the corresponding MG mixture solution was preheated at 80\u0026deg;C and applied on the base of the geometry that was pre-set at 80\u0026deg;C, then, using the true gap function, the plate of the geometry was set on the sample surface at the initial gap position in 300 \u0026micro;m. After stabilizing the sample temperature for 20 min at 80\u0026deg;C, the system was cooled at 10\u0026deg;C/min until achieving 5\u0026deg;C while measuring the elastic (G\u0026prime;) and loss (G\u0026Prime;) modulus. Then we continued measuring G\u0026rsquo; and G\u0026rdquo; under isothermal conditions (5\u0026deg;C) during 3 h, always applying conditions within the linear viscoelastic region (LVR) of the system. The LVR conditions were previously determined from strain (γ) sweeps obtained over the entire temperature interval (80\u0026deg;C to 2\u0026deg;C) applying a frequency of 1 Hz.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003e2.4. Statistical analysis\u003c/h2\u003e \u003cp\u003eThe effect of the treatment conditions on the thermal and rheological properties evaluated was analyzed through ANOVA and contrast between the treatment means using the STATISTICA V 12 (StatSoft Inc., Tulsa, OK).\u003c/p\u003e \u003c/div\u003e"},{"header":"3. RESULTS AND DISCUSION","content":"\u003cp\u003eThe phase diagrams for the C18:C14, C18:C16, and the C18:C22 mixtures in vegetable and mineral oil are shown in Figs.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e and \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e, respectively. As stated in the methodology, the phase diagrams for the MG binary mixtures in each type of oil were constructed as a function of both, the molar fractions of C18 and the corresponding molar fractions of C14, C16 or C22 in the MG mixture (Figs.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e and \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e). The behavior of the phase diagrams was established based on the corresponding crystallization and melting thermograms for the C18:C14, C18:C16, and the C18:C22 mixtures in the vegetable and the mineral oil (shown in Figs.\u0026nbsp;1SM to 3SM), and on the phase diagrams for MG oil solutions recently reported by our group [\u003cspan class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e\n\u003cp\u003e\u003cspan\u003e\u003c/span\u003e\u003c/p\u003e\n\u003ch2\u003e\u003cstrong\u003e3.1 Phase transitions of the C14, C16, C18, and C22 oil solutions at a molar fraction of 1.0\u003c/strong\u003e\u003c/h2\u003e\n\u003cp\u003e\u003c/p\u003e\n\u003cp\u003eUnder the cooling-heating conditions used in this study the thermograms of the 8% vegetable and mineral oil solutions of C16, C18, and C22 (i.e., corresponding to a molar fraction of 1.0 for C16, C18, and C22) showed the reversible L\u0026alpha; ⇄ sub-\u0026alpha;1 ⇄ sub-\u0026alpha;2 phase transitions (Figs.\u0026nbsp;1SM to 3SM). In line with our previous study [\u003cspan class=\"CitationRef\"\u003e8\u003c/span\u003e], the sub-\u0026alpha;2 phase transition occurred just in the vegetable or mineral oil solutions of MGs with esterified fatty acids of 16 or more carbons. The sub-\u0026alpha;2 phase did not occur during the cooling of the vegetable or mineral oil solutions of the binary mixtures of C16, C18, and C22 studied. Somehow the development of a mixed lamellar structure by the binary mixture of MGs limited the formation of the sub-\u0026alpha;2 phase (\u003cem\u003evide infra\u003c/em\u003e). The temperature for the sub-\u0026alpha;2 phase transition in the vegetable oil, indicated with an arrow in the corresponding phase diagrams at 1.0 molar fraction for C16, C18, and C22 (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e), was 21.02\u0026deg;C (\u0026plusmn;\u0026thinsp;0.11\u0026deg;C), 23.22\u0026deg;C (\u0026plusmn;\u0026thinsp;0.03\u0026deg;C), and 48.64\u0026deg;C (\u0026plusmn;\u0026thinsp;1.07\u0026deg;C), respectively. In the mineral oil the sub-\u0026alpha;2 phase transition temperature for the 1.0 molar fraction of C16, C18, and C22 occurred at lower temperatures (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05), specifically at 17.79\u0026deg;C (\u0026plusmn;\u0026thinsp;0.31\u0026deg;C), 20.50\u0026deg;C (\u0026plusmn;\u0026thinsp;0.08\u0026deg;C), and 41.50\u0026deg;C (\u0026plusmn;\u0026thinsp;1.69\u0026deg;C), respectively. As previously stated, the sub-\u0026alpha;1 \u0026rarr; sub-\u0026alpha;2 transition seems to be associated with the crystallization of a rotator phase remnant after the initial crystallization of the aliphatic chains in the L\u0026alpha; phase of the MGs [\u003cspan class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e9\u003c/span\u003e]. Our results indicated that, in the mineral oil the crystallization of the remnant rotator phase for the development of the sub-\u0026alpha;2 phase by the C16, C18, and C22, required higher supercooling than in the vegetable oil. In contrast to the behavior observed with C16, C18, and C22 oil solutions at 1.0 molar fraction, the cooling and heating thermogram for the C14 solution in both types of oils just showed the development of the isotropic ⇄ L\u0026alpha; ⇄ sub-\u0026alpha; transitions. However, it is important to note that the heating thermogram for the C14 at 1.0 molar fraction in vegetable oil showed the presence of a small additional endotherm at a temperature above the endotherm associated with the L\u0026alpha; phase (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003eSM, panel B). This endotherm was present in the C14 mineral oil solution at 1.0 molar fraction (i.e., 0:8 C18:C14 mixture), and particularly evident in the 7:1 and 6:2 C18:C14 mixtures also (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003eSM, panel D). Based on studies done by Lutton [\u003cspan class=\"CitationRef\"\u003e7\u003c/span\u003e], Malkin and Shurbagy [\u003cspan class=\"CitationRef\"\u003e19\u003c/span\u003e] and our previous results with neat C14 and C14 oil solutions [\u003cspan class=\"CitationRef\"\u003e8\u003c/span\u003e], the endotherm observed in the vegetable and mineral oil solutions of the 0:8 binary mixture of C18:C14 (i.e., 1.0 molar fraction) was associated with the melting of a \u0026beta; phase. This \u0026beta; phase ought to be developed during the cooling/heating conditions applied from C14 through a sub-\u0026alpha; to \u0026beta; polymorphic transition [\u003cspan class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e20\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e21\u003c/span\u003e]. Since the development of the \u0026beta; phase in the 0:8 binary mixture of C18:C14 (and in the 7:1 and 6:2 C18:C14 binary mixtures; see further discussion) came from a polymorphic transition, the development of the \u0026beta; phase was not included in the corresponding phase diagrams.\u003c/p\u003e\n\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\n \u003ch2\u003e3.2. Phase transitions of the C18:C14, C18:C16, and C18:C22 binary mixtures.\u003c/h2\u003e\n \u003cp\u003eIndependent of the type of oil used, under the cooling-heating conditions applied the cooling and heating thermograms for the C18:C14, C18:C16 and the C18:C22 mixtures at the 7:1, 6:2, 5:3, 4:4, 3:5, 2:6, and 1:7 proportions (i.e., corresponding to molar fractions of C18 lower than 1.0) showed the crystallization exotherms and corresponding melting endotherms associated just with the L\u0026alpha; and the sub-\u0026alpha; transitions (Figs.\u0026nbsp;1SM to 3SM). The presence of just one crystallization exotherm and melting endotherm associated with the L\u0026alpha; phase transition, indicated that upon cooling from the isotropic phase the binary mixtures of MGs (i.e., C18:C14, C18:C16 and C18:C22) developed a mixed lamellar organization (i.e., the L\u0026alpha; phase). Upon further cooling the mixed L\u0026alpha; phase developed the sub-\u0026alpha; phase (i.e., the sub-\u0026alpha;1 phase) through the crystallization of the alkyl chains in the mixed lamella. Nevertheless, the corresponding thermograms of the binary mixtures in the vegetable and mineral oil did not show the development of the sub-\u0026alpha;2 phase at any of the proportions studied (Figs.\u0026nbsp;1SM to 3SM). As already stated, the development of mixed lamellar structures by the C18:C14, C18:C16 and C18:C22 binary mixtures somehow limited the formation of the sub-\u0026alpha;2 phase. As already indicated, independent of the type of oil, the heating thermograms of the C18:C14 binary mixture at 7:1 and 6:2 proportions (Fig.\u0026nbsp;1SM panels B and D), showed an additional endotherm above the melting endotherm for the L\u0026alpha; phase. Additionally, at the 5:3 and 4:4 proportions we noted that the melting endotherm for the L\u0026alpha; phase showed a shoulder (Fig.\u0026nbsp;1SM panel B). This behavior was associated with the melting of a \u0026beta; phase, tentatively developed through a polymorphic transition from the sub-\u0026alpha; phase of C18 [\u003cspan class=\"CitationRef\"\u003e21\u003c/span\u003e\u0026ndash;\u003cspan class=\"CitationRef\"\u003e22\u003c/span\u003e]. Within this context, we considered that in the vegetable oil the C18:C14 system at the 7:1, 6:2, 5:3 and 4:4 proportions the melting of the L\u0026alpha; and the \u0026beta; phases occurred within the same temperature interval making hard to establish a reliable phase transition for the L\u0026alpha; phase. Consequently, the phase diagram for the C18:C14 in the vegetable oil could not include a phase transition temperature for the L\u0026alpha; phase for the whole concentration interval studied (Fig. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003eA). Therefore, in the phase diagram for the C18:C14 in the vegetable oil (Fig. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003eA) the L\u0026alpha; phase transition temperature tentatively occurring at C18 molar fractions higher than 0.4 (i.e., C14 molar fractions lower than 0.6) was indicated just with a dotted line. As established by Lutton [\u003cspan class=\"CitationRef\"\u003e7\u003c/span\u003e] and our own studies [\u003cspan class=\"CitationRef\"\u003e8\u003c/span\u003e], C14 is prone to go through a sub-\u0026alpha; to \u0026beta; polymorphic transition in the neat state and in oil solutions. Additionally, Chen and Terentjev [\u003cspan class=\"CitationRef\"\u003e22\u003c/span\u003e] observed that after 5\u0026ndash;7 days of storage at 26\u0026deg;C neat C18 developed a \u0026beta; polymorph also through a polymorphic transition from the sub-\u0026alpha; phase. Then, the results obtained indicated that in the 7:1, 6:2, 5:3 and 4:4 C18:C14 binary mixtures the presence of C14 in the mixed lamella could promote the development of the \u0026beta; phase from the C18, particularly in the vegetable oil. This because the heating thermograms just for C18 in both types of oil, did not show the presence of the endotherm associated with the \u0026beta; polymorph. Since the development of the \u0026beta; phase in the C18:C14 binary mixture (0:8, 7:1, 6:2, 5:3 and 4:4 proportions) came from a polymorphic transition, the development of the \u0026beta; phase was not included in the C18:C14 phase diagram (Fig. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003eA).\u003c/p\u003e\n \u003cp\u003eThe phase diagrams were done at each MG proportion keeping a total MG concentration of 8% (wt/wt). Within this context we observed that, independent of the MG binary mixture and the type of oil, the phase transition temperature for the mixed L\u0026alpha; phase (T\u0026deg;-L\u0026alpha;) apparently behaved independent of the C18 molar fraction (Figs. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e and \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e). Nevertheless, a more in-deep analysis of the phase diagrams showed that, for the C18:C14 in the mineral oil and the C18:16 in both types of oil, the T\u0026deg;-L\u0026alpha; had a quadratic increase as a direct function of the C18 molar fraction (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05). Thus, as the concentration of the MG with the fatty acid of higher number of carbons (i.e., longer aliphatic chain) increased in the C18:C14 and the C18:16 binary mixtures, the phase transition temperature for the mixed L\u0026alpha; phase (i.e., the initial MGs self-assembly) showed a concave quadratic increase until achieving a maximum at a 1.0 molar fraction of C18 (Figs. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e and \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e panels A and B). Unfortunately, the behavior of T\u0026deg;-L\u0026alpha; for the C18:C14 in the vegetable oil could not be evaluated. As previously discussed at the 7:1, 6:2, 5:3 and 4:4 C18:C14 proportions the L\u0026alpha; and the \u0026beta; phases occurred within the same temperature interval. Consequently, we could not establish a reliable phase transition for the L\u0026alpha; phase at molar fractions of C18 higher than 0.4 (i.e., C14 molar fractions lower than 0.6). On the other hand, independent of the type of oil, the T\u0026deg;-L\u0026alpha; in the C18:22 phase diagrams showed a small but a significant concave quadratic increase as the C22 molar fraction increased (i.e., as the concentration of the MG with the longer aliphatic chain increased) until achieving a maximum at 1.0 molar fraction of C22 (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05). We explained the T\u0026deg;-L\u0026alpha; behavior in the MG binary mixtures considering that, besides the effect of the polarity of the OH groups, the temperature for the initial MGs self-assembly depended also on the MGs\u0026rsquo; aliphatic chains oil solubility. Thus, the higher the proportion of the MG with the longer aliphatic chain (i.e., the higher the molar fraction of C18 or C22 in the corresponding binary mixture) the lower the solubility of the mixed L\u0026alpha; phase in the oil and, subsequently the higher the T\u0026deg;-L\u0026alpha; (Figs. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e and \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e). It is important to recall that the closely packed bilayer organization of the mixed L\u0026alpha; phase it is a requirement for the further crystallization of the aliphatic chains in the mixed lamella (i.e., the L\u0026alpha; \u0026rarr; sub-\u0026alpha; transition). Consequently, the MGs\u0026rsquo; composition of the L\u0026alpha; phase ought to determine the temperature for the sub-\u0026alpha; phase transition. This because if the MGs\u0026rsquo; composition of the L\u0026alpha; phase resulted in an efficient aliphatic chain packing, the T\u0026deg;-sub-\u0026alpha; would occur at higher temperature that if the L\u0026alpha; phase had a less efficient aliphatic chain packing. Through experimental analysis (i.e., calorimetry and X-ray scattering) and computer simulation of tripalmitin-tristearin mixtures, Pizzirusso et al. [\u003cspan class=\"CitationRef\"\u003e23\u003c/span\u003e] showed that the crystallization temperature followed a eutectic behavior. The crystallization behavior of the tripalmitin-tristearin mixtures was associated with the packing efficiency of the triglycerides in the mixed crystal. The authors concluded that at the eutectic point, the tripalmitin-tristearin composition in the mixed crystal resulted in less efficient chain packing and, subsequently, in a lower melting temperature. The authors associated the decrease in the melting temperature at the eutectic composition (i.e., 70% tripalmitin-30% tristearin) with a balance between enthalpic and entropic effects resulting from the packing efficiency between the triglycerides that finally determined the eutectic temperature [\u003cspan class=\"CitationRef\"\u003e23\u003c/span\u003e]. Within this framework, we concluded that the eutectic behavior of the T\u0026deg;\u003csub\u003esub\u0026minus;\u0026alpha;\u003c/sub\u003e observed in both types of oils by the C18:C14, C18:16, and C18:C22 binary mixtures (Figs. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e and \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e), was associated with the MG composition of the mixed L\u0026alpha; phase and its effect in the aliphatic chain packing efficiency throughout the lamella. Thus, we considered that at the eutectic temperature for the sub-\u0026alpha; transition (T\u0026deg;\u003csub\u003eE\u003c/sub\u003e sub-\u0026alpha;), the aliphatic chains packing throughout the mixed lamella was the least efficient. This possible because at the molar composition of the mixed L\u0026alpha; phase, the difference in length between the aliphatic chains of the MGs resulted in the least efficient chains packing of that developed by any other MG molar fraction. Therefore, the composition of the mixed crystal at the corresponding T\u0026deg;\u003csub\u003eE\u003c/sub\u003e sub-\u0026alpha; for the MG binary mixtures studied (Table \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e), provided over all the MG proportions the lowest melting temperature for the sub-\u0026alpha; phase. These results applied independent of the type of oil and the binary mixture of MG. We considered that the composition of the mixed crystal at T\u0026deg;\u003csub\u003eE\u003c/sub\u003e sub-\u0026alpha; was closely associated with the molar MG composition of the oil solution at the corresponding eutectic point. Within this context, Table \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e includes the tentative molar MG composition of the mixed crystal at the T\u0026deg;\u003csub\u003eE\u003c/sub\u003e sub-\u0026alpha;, and shows that the T\u0026deg;\u003csub\u003eE\u003c/sub\u003e sub-\u0026alpha; increased in the following order: C18:C22\u0026thinsp;\u0026gt;\u0026thinsp;C18:C16\u0026thinsp;\u0026gt;\u0026thinsp;C18:C14 (P\u0026thinsp;\u0026lt;\u0026thinsp;0.01; Table \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e). These results indicated that, independent of the type of oil, the lower the aliphatic chain length of the MG that complemented with C18 the binary mixture, the lower the T\u0026deg;\u003csub\u003eE\u003c/sub\u003e sub-\u0026alpha; and the higher the molar fraction of that MG that resulted in a less efficient chain packing in the mixed crystal. From the above and considering the MG oil solubility, as the temperature decreased in an oil solution of a binary MG mixture with a high C18 molar fraction, the MG driving the molecular self-assembly from the isotropic phase (i.e., isotropic phase\u0026rarr;L\u0026alpha; phase) was C18. As the C18 molar fraction decreased in the binary mixture, the decrease in temperature resulted in more C14, C16 or C22 molecules integrated into the C18 lamella, resulting in less efficient MGs packing and lower L\u0026alpha;, and particularly, lower sub-\u0026alpha; transition temperatures. This process occurred until at the binary MG composition associated at T\u0026deg;\u003csub\u003eE\u003c/sub\u003e sub-\u0026alpha;, the least efficient MG packing was achieved (i.e., the eutectic point). Within this context, the behavior of the transition temperature for the sub-\u0026alpha; as in the C18:C14, C18:16, and C18:C22 binary mixtures, was the result of the MGs packing as the C14, C16 or C22 molecules were integrated into the C18 lamella. This was indicated in the corresponding phase diagram by using first C18 in the nomenclature used to point out the respective MG phase, i.e., C18-C14 L\u0026alpha;, C18-C14 sub-\u0026alpha;, C18-C16 L\u0026alpha;, C18-C16 sub-\u0026alpha;, C18-C22 L\u0026alpha;, C18-C22 sub-\u0026alpha; (Figs. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e and \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e). At C18 molar fractions in the binary mixture lower than the one associated with the eutectic point (Table \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e), the MG that drove the isotropic phase\u0026rarr;L\u0026alpha; and the L\u0026alpha;\u0026rarr;sub-\u0026alpha; transitions was, depending on the MG binary mixture, C14, C16, or C22. We indicated this in the corresponding phase diagrams by using first C14, C16 or C22 in the nomenclature used to point out the respective phase, i.e., C14-C18 L\u0026alpha;, C14-C18 sub-\u0026alpha;, C16-C18 L\u0026alpha;, C16-C18 sub-\u0026alpha;, C22-C18 L\u0026alpha;, C22-C18 sub-\u0026alpha; (Figs. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e and \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e\n \u003cp\u003e\u003c/p\u003e\u0026nbsp;\u003ctable id=\"Tab1\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eEutectic temperature (T\u0026deg;\u003csub\u003eE\u003c/sub\u003e) for the sub-\u0026alpha; phase (T\u0026deg;\u003csub\u003eE\u003c/sub\u003e sub-\u0026alpha;) and molar fraction composition for the mixed sub-\u0026alpha; phase at T\u0026deg;\u003csub\u003eE\u003c/sub\u003e for each of the binary MG mixtures studied in vegetable and mineral oil.\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"2\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003eC18:C14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003eC18:C16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003eC18:C22\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003esub-\u0026alpha; phase molar fraction composition at T\u0026deg;\u003csub\u003eE\u003c/sub\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eT\u0026deg;\u003csub\u003eE\u003c/sub\u003e sub-\u0026alpha;\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\n \u003cp\u003e(\u0026deg;C)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003esub-\u0026alpha; phase molar fraction composition at T\u0026deg;\u003csub\u003eE\u003c/sub\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eT\u0026deg;\u003csub\u003eE\u003c/sub\u003e sub-\u0026alpha;\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\n \u003cp\u003e(\u0026deg;C)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003esub-\u0026alpha; phase molar fraction composition at T\u0026deg;\u003csub\u003eE\u003c/sub\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eT\u0026deg;\u003csub\u003eE\u003c/sub\u003e sub-\u0026alpha;\u003c/p\u003e\n \u003cp\u003e(\u0026deg;C)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eVegetable oil\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003e0.250 C18\u003c/p\u003e\n \u003cp\u003e0.750 C14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-1.00\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\n \u003cp\u003e(0.01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003e0.375 C18\u003c/p\u003e\n \u003cp\u003e0.625 C16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e12.45\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\n \u003cp\u003e(0.15)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003e0.750 C18\u003c/p\u003e\n \u003cp\u003e0.250 C22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e20.64\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\n \u003cp\u003e(0.22)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMineral oil\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-2.76\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e\n \u003cp\u003e(0.16)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e8.58\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e\n \u003cp\u003e(0.06)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e20.64\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\n \u003cp\u003e(0.21)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003cp\u003e\u003c/p\u003e\n \u003cp\u003e\u003cbr\u003e\u003c/p\u003e\n \u003cp\u003e\u003csup\u003ea\u003c/sup\u003e Eutectic temperature for the sub-\u0026alpha; phase reported as the mean and standard deviation (within brackets) of two independent determinations (n\u0026thinsp;=\u0026thinsp;2).\u003c/p\u003e\n \u003cp\u003e\u003csup\u003eb, c\u003c/sup\u003e For the same binary MG mixture a different superscript indicates a significant effect of the type of oil on the T\u0026deg;\u003csub\u003eE\u003c/sub\u003e sub-\u0026alpha; (P\u0026thinsp;\u0026lt;\u0026thinsp;0.01).\u003c/p\u003e\u003cspan\u003e\n \u003ch2\u003e\u003cstrong\u003e3.3 Rheological properties of the MGs and the MG binary mixtures in the vegetable and mineral oil\u003c/strong\u003e\u003c/h2\u003e\n \u003c/span\u003e\n \u003cp\u003eFigure \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e shows the rheograms for the vegetable and mineral oil systems at 1.0 molar fraction of C14, C16, C18 and C22 during cooling (Figs.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003eA and \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003eB) and isothermal (Figs.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003eC and \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003eD) conditions. The \u003cem\u003eG\u0026rsquo;\u003c/em\u003e behavior during cooling was explained associating the MGs\u0026rsquo; phase transitions through the superimposition of the cooling \u003cem\u003eG\u0026rsquo;\u003c/em\u003e rheograms on the corresponding cooling thermograms. The resulting graphs for some of the MGs studied (i.e., C16, C18, and C22) are shown in Figs.\u0026nbsp;4SM and 5SM (Supplementary Material). These results showed that, independent of the type of oil and the MG, the initial \u003cem\u003eG\u0026rsquo;\u003c/em\u003e increment observed during cooling of the MGs oil solutions was associated with the development of the isotropic phase\u0026rarr;L\u0026alpha; transition (Figs.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003eA and \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003eB). The \u003cem\u003eG\u0026rsquo;\u003c/em\u003e onset (i.e., the onset of the MGs\u0026rsquo; self-assembly) occurred at higher temperature as the number of carbons of the aliphatic chain in the MG increased (Figs.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003eA and \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003eB). This behavior was observed independent of the type of oil. As previously observed, in MG oil solutions the temperature for the onset of the molecular self-assembly increases as the number of carbons of the esterified fatty acid increased [\u003cspan class=\"CitationRef\"\u003e8\u003c/span\u003e]. As cooling continued the crystallization of the aliphatic chains in the lamella (i.e., the L\u0026alpha;\u0026rarr;sub-\u0026alpha;1 phase transition) predominated over the L\u0026alpha; phase formation (i.e., the isotropic phase\u0026rarr; L\u0026alpha; phase transition). Additionally, as already discussed, in MGs with esterified fatty acids of 16 carbons and longer a sub-\u0026alpha;2 phase transition occurs at lower temperatures than the sub-\u0026alpha;1 phase [\u003cspan class=\"CitationRef\"\u003e8\u003c/span\u003e]. The sub-\u0026alpha;2 phase transition might be associated with the crystallization of a rotator phase remnant in the aliphatic chains of the MGs in the lamella [\u003cspan class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e9\u003c/span\u003e]. Therefore, as cooling continued the crystallization heat released by the sub-\u0026alpha;1 and sub-\u0026alpha;2 phase transitions resulted in partial melting of the already crystallized MGs until further cooling dissipated the heat generated. The overall effect was a concomitant reduction on the \u003cem\u003eG\u0026rsquo;\u003c/em\u003e growth until the elasticity of the systems achieved a tentative plateau even before attaining 5\u0026deg;C. It is important to note that C14 does not develop the sub-\u0026alpha;2 phase [\u003cspan class=\"CitationRef\"\u003e7\u003c/span\u003e], and subsequently in the C14 system at 1.0 Molar fraction no additional crystallization heat was generated at temperatures below the sub-\u0026alpha;1 phase transition. This might partially explain the \u003cem\u003eG\u0026rsquo;\u003c/em\u003e increase observed in the C14 system at temperatures below the sub-\u0026alpha;1 phase transition, achieving \u003cem\u003eG\u0026rsquo;\u003c/em\u003e values similar to or higher than the C16 and the C18 systems (Figs.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003eA and \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003eB). However, as previously discussed C14 is prone to go through a sub-\u0026alpha; to \u0026beta; polymorphic transition [\u003cspan class=\"CitationRef\"\u003e6\u003c/span\u003e\u0026ndash;\u003cspan class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e20\u003c/span\u003e\u0026ndash;\u003cspan class=\"CitationRef\"\u003e21\u003c/span\u003e]. Therefore, the development of the \u0026beta; polymorph during cooling might also be associated with the \u003cem\u003eG\u0026rsquo;\u003c/em\u003e increment observed in the C14 system at temperatures below the sub-\u0026alpha;1 phase transition (Figs.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003eA and \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003eB).\u003c/p\u003e\n \u003cp\u003eThe behavior of \u003cem\u003eG\u0026rsquo;\u003c/em\u003e under isothermal conditions (5\u0026deg;C) for the vegetable and mineral oil systems at 1.0 molar fraction of C14, C16, C18 and C22 is shown in Figs. \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003eC and \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003eD. Although \u003cem\u003eG\u0026rdquo;\u003c/em\u003e was not included in the isothermal rheograms shown in Figs. \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003eC and \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003eD, the results showed that, independent of the type of oil and the MG, the \u003cem\u003eG\u0026rsquo;\u003c/em\u003e of the oleogels was always higher than \u003cem\u003eG\u0026rdquo;\u003c/em\u003e during the whole isothermal period (i.e., 180 min). Although at 5\u0026deg;C we did not determine frequency sweeps in the 8% C14, C16, C18 and C22 oleogels, based on previous studies involving rheological measurements of vegetable oil oleogels formulated with different concentrations of C18 and a commercial MG (0.5\u0026ndash;8% wt/wt) [\u003cspan class=\"CitationRef\"\u003e6\u003c/span\u003e], we considered that the oleogels developed in the vegetable and mineral oil with 8% of C14, C16, C18, and C22 were true gels. Under isothermal conditions (5\u0026deg;C) the \u003cem\u003eG\u0026rsquo;\u003c/em\u003e for the MGs systems in the vegetable oil tended to achieve a plateau as a function of time, attaining higher \u003cem\u003eG\u0026rsquo;\u003c/em\u003e values as a direct function of the length of the aliphatic chain of the MG (Fig. \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003eC). Although in the mineral oil the MGs systems also tended to achieve a \u003cem\u003eG\u0026rsquo;\u003c/em\u003e plateau, for the same MG system we observed different rheological behavior. Working with similar vegetable and mineral oils, Aguilar-Z\u0026aacute;rate et al. [\u003cspan class=\"CitationRef\"\u003e24\u003c/span\u003e] reported that a commercial MG was more soluble in vegetable oil than in mineral oil. Additionally, these authors showed that after 24 h at 15\u0026deg;C the MG in a 2% vegetable oil solution crystallized as small acicular crystals, while in the mineral oil the MG crystallized as larger rod-shaped crystals. As previously indicated, the mineral oil was essentially composed of saturated (linear and branched) \u003cem\u003en\u003c/em\u003e-alkanes with a hydrocarbon chain between 15 and 50 carbons. In contrast, the vegetable oil was mainly composed by triacylglycerides (95\u0026ndash;98%) and some additional minor components like mono-, di-acylglycerides, and free fatty acids. Then, mineral oil had lower relative polarity than vegetable oils. We consider that the relative polarity effect on the MG\u0026rsquo;s oil solubility affected the MG\u0026rsquo;s crystallization kinetics and the MG\u0026rsquo;s crystal habit. The overall result was that for the same MG we obtained a different rheological behavior in each type of oil. Thus, in the vegetable oil the \u003cem\u003eG\u0026rsquo;\u003c/em\u003e of the oleogels increased as a function of time achieving a plateau. L\u0026oacute;pez-Mart\u0026iacute;nez et al. observed similar rheological behavior for vegetable oil oleogels developed with C18 at concentrations\u0026thinsp;\u0026ge;\u0026thinsp;2% [\u003cspan class=\"CitationRef\"\u003e6\u003c/span\u003e]. These authors showed that the increase in G\u0026rsquo; as a function of time at 5\u0026deg;C, could not be associated with an increase in the solid content of the oleogel since this value (measured by NMR) remained constant during the 180 min at 5\u0026deg;C. The authors associated the \u003cem\u003eG\u0026rsquo;\u003c/em\u003e behavior with an increase in the size of the plate-like shaped crystals observed in the C18 oleogels as function of time 5\u0026deg;C [\u003cspan class=\"CitationRef\"\u003e6\u003c/span\u003e]. In contrast, in the mineral oil the \u003cem\u003eG\u0026rsquo;\u003c/em\u003e of the C16 and C18 oleogels showed a relative constant behavior during the whole isothermal period. However, under isothermal conditions the C14 oleogels showed an increase in \u003cem\u003eG\u0026rsquo;\u003c/em\u003e as a function of time until achieving a plateau after \u0026asymp;\u0026thinsp;165 min at 5\u0026deg;C (Fig. \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003eD). As already indicated C14 is prone to develop a sub-\u0026alpha; \u0026rarr; \u0026beta; phase polymorphic transition [\u003cspan class=\"CitationRef\"\u003e6\u003c/span\u003e\u0026ndash;\u003cspan class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e20\u003c/span\u003e\u0026ndash;\u003cspan class=\"CitationRef\"\u003e21\u003c/span\u003e], and our results showed that this transition occurred more evident in mineral oil than in vegetable oil (Fig. 1SM panels D and C, respectively). Therefore, the increase in \u003cem\u003eG\u0026rsquo;\u003c/em\u003e, particularly observed in the C14 oleogels developed in the mineral oil, might be associated with the \u0026beta; phase formation during cooling (Fig. \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003eB) and continuing under isothermal conditions (Fig. \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003eD). On the other hand, the C22 oleogels in mineral oil were the only ones that under isothermal conditions showed a pronounced curvilinear decrease until achieving a plateau after \u0026asymp;\u0026thinsp;100 min (Fig. \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003eD). Unfortunately, we did not have enough C22 to determine the solid content of the oleogel as a function of time at 5\u0026deg;C to evaluate if the MG with the longest esterified fatty acid solubilized in the mineral oil as a function of time resulting in a \u003cem\u003eG\u0026rsquo;\u003c/em\u003e decrease. Nevertheless, we considered that this explanation was improbable mainly because previous studies [\u003cspan class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e24\u003c/span\u003e] showed that C22 has lower solubility in mineral oil than in vegetable oil. Additionally, the C22 oleogels in vegetable oil did not show the decrease in \u003cem\u003eG\u0026rsquo;\u003c/em\u003e as a function of time at 5\u0026deg;C (Fig. \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003eC). Evidently, we need to do additional experiments (i.e., microstructural analysis of the oleogels under cooling and isothermal conditions) to explain the rheological behavior of the MG oleogels fully.\u003c/p\u003e\n \u003cp\u003e\u003c/p\u003e\u0026nbsp;\u003ctable id=\"Tab2\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003e\u003cem\u003eG\u0026rsquo;\u003c/em\u003e values at 5\u0026deg;C (\u003cem\u003eG\u0026rsquo;\u003c/em\u003e\u003csub\u003e5\u0026deg;C\u003c/sub\u003e) for the oleogels developed in the vegetable or mineral oil at 1.0 molar fraction of C14, C16, C18, and C22, and for the oleogels developed with the C18:C14, C18:C16, and C18:C22 binary mixtures at the molar fraction composition associated with the eutectic point (see Table \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\" colspan=\"7\"\u003e\n \u003cp\u003e\u003cem\u003eG\u0026rsquo;\u003c/em\u003e\u003csub\u003e5\u0026deg;C\u003c/sub\u003e\u003c/p\u003e\n \u003cp\u003e(Pa x 10\u003csup\u003e3\u003c/sup\u003e)\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMolar fraction of the corresponding MG\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC18:C14\u003c/p\u003e\n \u003cp\u003e0.250 C18\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e\n \u003cp\u003e0.750 C14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC18:C16\u003c/p\u003e\n \u003cp\u003e0.375 C18\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e\n \u003cp\u003e0.625 C16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC18:C22\u003c/p\u003e\n \u003cp\u003e0.750 C18\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e\n \u003cp\u003e0.250 C22\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eVegetable oil\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e53.16\u003csup\u003eb, e\u003c/sup\u003e\u003c/p\u003e\n \u003cp\u003e(0.47)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e71.79\u003csup\u003eb, k\u003c/sup\u003e\u003c/p\u003e\n \u003cp\u003e(0.98)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e86.37\u003csup\u003eb, l\u003c/sup\u003e\u003c/p\u003e\n \u003cp\u003e(1.85)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e128.40\u003csup\u003eb, m\u003c/sup\u003e\u003c/p\u003e\n \u003cp\u003e(1.24)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1507.59\u003csup\u003eb, n\u003c/sup\u003e\u003c/p\u003e\n \u003cp\u003e(4.09)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e369.27\u003csup\u003eb, o\u003c/sup\u003e\u003c/p\u003e\n \u003cp\u003e(3.31)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e687.96\u003csup\u003eb, p\u003c/sup\u003e\u003c/p\u003e\n \u003cp\u003e(5.91)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMineral oil\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e67.99\u003csup\u003ec, j\u003c/sup\u003e\u003c/p\u003e\n \u003cp\u003e(0.82)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e37.80\u003csup\u003ec, k\u003c/sup\u003e\u003c/p\u003e\n \u003cp\u003e(0.22)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e49.14\u003csup\u003ec, l\u003c/sup\u003e\u003c/p\u003e\n \u003cp\u003e(0.10)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e22.69\u003csup\u003ec, m\u003c/sup\u003e\u003c/p\u003e\n \u003cp\u003e(0.49)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e595.31\u003csup\u003ec, n\u003c/sup\u003e\u003c/p\u003e\n \u003cp\u003e(1.57)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e56.11\u003csup\u003ec, o\u003c/sup\u003e\u003c/p\u003e\n \u003cp\u003e(1.39)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e154.04\u003csup\u003ec, p\u003c/sup\u003e\u003c/p\u003e\n \u003cp\u003e(8.11)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"9\"\u003e\u003csup\u003ea\u003c/sup\u003e The \u003cem\u003eG\u0026rsquo;\u003c/em\u003e\u003csub\u003e5\u0026deg;C\u003c/sub\u003e and corresponding standard deviation were determined from two independent determinations (n\u0026thinsp;=\u0026thinsp;2)\u003cbr\u003e\n \u003cp\u003e\u003csup\u003eb, c\u003c/sup\u003e For the same MG, values with different first superscript indicates a significant effect of the type of oil on the \u003cem\u003eG\u0026rsquo;\u003c/em\u003e\u003csub\u003e5\u0026deg;C\u003c/sub\u003e of the oleogel (P\u0026thinsp;\u0026lt;\u0026thinsp;0.01).\u003c/p\u003e\n \u003cp\u003e\u003csup\u003ed\u003c/sup\u003e For the corresponding binary MG mixture this was the molar fraction composition for the mixed sub-\u0026alpha; phase at T\u0026deg;\u003csub\u003eE\u003c/sub\u003e\u003c/p\u003e\n \u003cp\u003e\u003csup\u003ee\u0026minus;k\u003c/sup\u003e For the same type of oil, \u003cem\u003eG\u0026rsquo;\u003c/em\u003e\u003csub\u003e5\u0026deg;C\u003c/sub\u003e values with different second superscript indicates a significant effect of the MG system on the \u003cem\u003eG\u0026rsquo;\u003c/em\u003e\u003csub\u003e5\u0026deg;C\u003c/sub\u003e of the corresponding oleogel (P\u0026thinsp;\u0026lt;\u0026thinsp;0.01).\u003c/p\u003e\u003cbr\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n \u003cp\u003e\u003c/p\u003e\n \u003cp\u003eTo evaluate the type of oil effect on the elastic properties of the C14, C16, C18, and C22 oleogels, we determined, in each of the two independent isothermal rheograms an average \u003cem\u003eG\u0026rsquo;\u003c/em\u003e using the measurements from the last 5 min at 5\u0026deg;C. With these values we then calculated, for each of the MG oleogels, a mean \u003cem\u003eG\u0026rsquo;\u003c/em\u003e (\u003cem\u003eG\u0026rsquo;\u003c/em\u003e\u003csub\u003e5\u0026deg;C\u003c/sub\u003e) and associated standard deviation (Table \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e). The corresponding statistical analysis showed that, except the C14 oleogels, the \u003cem\u003eG\u0026rsquo;\u003c/em\u003e\u003csub\u003e5\u0026deg;C\u003c/sub\u003e of the C16, C18, and C22 oleogels in vegetable oil was significantly higher than the \u003cem\u003eG\u0026rsquo;\u003c/em\u003e\u003csub\u003e5\u0026deg;C\u003c/sub\u003e of the corresponding MG oleogel in the mineral oil (P\u0026thinsp;\u0026lt;\u0026thinsp;0.01). Given the rheological behavior observed by the C22 oleogels in the mineral oil (Fig. \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003eD), the \u003cem\u003eG\u0026rsquo;\u003c/em\u003e\u003csub\u003e5\u0026deg;C\u003c/sub\u003e for the C22 oleogels in vegetable oil was particularly higher than the one obtained by the C22 oleogels in the mineral oil (Table \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e), this. On the other hand, the \u003cem\u003eG\u0026rsquo;\u003c/em\u003e\u003csub\u003e5\u0026deg;C\u003c/sub\u003e of the C14 oleogels developed in the mineral oil was higher than the \u003cem\u003eG\u0026rsquo;\u003c/em\u003e\u003csub\u003e5\u0026deg;C\u003c/sub\u003e of the C14 oleogels formulated with vegetable oil (P\u0026thinsp;\u0026lt;\u0026thinsp;0.01), tentatively because in the mineral oil oleogels the C14 developed higher amounts of the \u0026beta; phase. The overall result was that, in the vegetable oil the C22 oleogels achieved the highest \u003cem\u003eG\u0026rsquo;\u003c/em\u003e\u003csub\u003e5\u0026deg;C\u003c/sub\u003e and the C14 oleogels the lowest \u003cem\u003eG\u0026rsquo;\u003c/em\u003e\u003csub\u003e5\u0026deg;C\u003c/sub\u003e while the opposite occurred with the corresponding mineral oil oleogels (Table \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e\n \u003cp\u003eFinally, using vegetable and mineral oil solutions with MG proportions selected from the ones used in the C18:C14, C18:C16, and C18:C22 phase diagrams (Figs. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e and \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e), we determined their rheological behavior using the same time-temperature conditions as with the C14, C16, C18 and C22 systems. This to evaluate the effect of the MG binary mixture composition on the rheological properties of the vegetable and mineral oil oleogels. It is important to note that these oleogels were done with the same total MG concentration (i.e., 8% wt/wt) as in the MG oil solutions used to determine the phase diagrams. The selected MG proportions from each MG binary mixture, included the one associated with the eutectic point (Table \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e) and MG proportions above and below the corresponding eutectic point. Within this context, Figs. \u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e to \u003cspan class=\"InternalRef\"\u003e11\u003c/span\u003e show the rheological profiles obtained at different MG proportions of the C18:C16 and C18:C22 systems in vegetable and mineral oil. Overall, the binary MG mixtures in each type of oil, including the 18:14 system (results not shown), showed similar rheological behavior during cooling (Figs. \u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e, \u003cspan class=\"InternalRef\"\u003e6\u003c/span\u003e, \u003cspan class=\"InternalRef\"\u003e8\u003c/span\u003e, and \u003cspan class=\"InternalRef\"\u003e10\u003c/span\u003e) as the one observed by the C14, C16, C18 and C22 systems (Fig. \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e). However, the binary MG mixtures showed one major difference in their rheological behavior with respect to the one observed by the C14, C16, C18 and C22 systems. This because after the \u003cem\u003eG\u0026rsquo;\u003c/em\u003e onset associated with the development of the L\u0026alpha; phase, the \u003cem\u003eG\u0026rsquo;\u003c/em\u003e showed a plateau followed by a second steady \u003cem\u003eG\u0026rsquo;\u003c/em\u003e increment and then by a second \u003cem\u003eG\u0026rsquo;\u003c/em\u003e plateau. This rheological behavior was observed in all the binary MG mixtures independent of the type of oil (Figs. \u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e, \u003cspan class=\"InternalRef\"\u003e6\u003c/span\u003e, \u003cspan class=\"InternalRef\"\u003e8\u003c/span\u003e, and \u003cspan class=\"InternalRef\"\u003e10\u003c/span\u003e). Always, the second \u003cem\u003eG\u0026rsquo;\u003c/em\u003e growth occurred below the temperature for the sub-\u0026alpha; phase transition (temperature indicated with an arrow in Figs. \u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e, \u003cspan class=\"InternalRef\"\u003e6\u003c/span\u003e, \u003cspan class=\"InternalRef\"\u003e8\u003c/span\u003e, and \u003cspan class=\"InternalRef\"\u003e10\u003c/span\u003e). It is important to recall that, in contrast with the 1.0 molar oil solutions of C16, C18, and C22, the cooling and heating thermograms of the binary MG mixtures in vegetable or mineral oil did not develop the sub-\u0026alpha;2 phase (Figs.\u0026nbsp;1SM to 3SM). It seemed that the mixed aliphatic chains packing hindered the crystallization of the rotator phase tentatively associated with the sub-\u0026alpha;2 transition [\u003cspan class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e8\u003c/span\u003e]. Consequently, in contrast with the \u003cem\u003eG\u0026rsquo;\u003c/em\u003e profile of the C16, C18, and C22 systems during cooling (Figs. \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003eA and \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003eB), the crystallization heat associated with the sub-\u0026alpha;2 transition did not affect the rheological behavior of the MG binary mixtures. The corresponding \u003cem\u003eG\u0026rsquo;\u003c/em\u003e behavior under isothermal conditions of the C18:C16 and C18:22 oleogels in vegetable and mineral oil are shown in Figs. \u003cspan class=\"InternalRef\"\u003e5\u003c/span\u003e, \u003cspan class=\"InternalRef\"\u003e7\u003c/span\u003e, \u003cspan class=\"InternalRef\"\u003e9\u003c/span\u003e and \u003cspan class=\"InternalRef\"\u003e11\u003c/span\u003e. As stated previously, we did not determine frequency sweeps of the oleogels to establish if the systems could be considered true gels. However, based on previous rheological studies done with vegetable oil oleogels developed with different concentrations (0.5\u0026ndash;8% wt/wt) of a commercial mixture of C16 and C18 [\u003cspan class=\"CitationRef\"\u003e6\u003c/span\u003e], we considered that the oleogels developed by the binary MG mixtures were true gels. Additionally, as with the C14, C16, C18, and C22 oleogels, independent of the type of oil, the \u003cem\u003eG\u0026rsquo;\u003c/em\u003e of the C18:C16 and C18:22 oleogels were always higher than \u003cem\u003eG\u0026rdquo;\u003c/em\u003e during the whole isothermal period (i.e., 180 min). Similar rheological behavior was observed by the C18:C14 oleogels (data not shown). Furthermore, independent of the type of oil, during the whole isothermal period most of the oleogels developed by the binary MG mixtures showed a relative constant \u003cem\u003eG\u0026rsquo;\u003c/em\u003e. Just the C18:C16 oleogel developed with a C18 molar fraction of 0.375 (Fig. \u003cspan class=\"InternalRef\"\u003e5\u003c/span\u003eB), the C18:C22 oleogel developed with a C18 molar fraction of 0.75 (Fig. \u003cspan class=\"InternalRef\"\u003e9\u003c/span\u003eB) both in vegetable oil, and the C18:C16 mineral oil oleogel developed with a C18 molar fraction of 0.125 (Fig. \u003cspan class=\"InternalRef\"\u003e7\u003c/span\u003eD) showed a \u003cem\u003eG\u0026rsquo;\u003c/em\u003e increment until achieving a plateau after 140\u0026ndash;160 min at 5\u0026deg;C. We considered that this \u003cem\u003eG\u0026rsquo;\u003c/em\u003e increment was associated with changes in the microstructural arrangement of the MG crystals rather than with additional MG crystallization occurring under isothermal conditions. It is important to make additional studies to explain this behavior, mainly because most of the oleogels showing this rheological behavior corresponded to those formulated with the MG composition associated with the eutectic point. After calculating the \u003cem\u003eG\u0026rsquo;\u003c/em\u003e\u003csub\u003e5\u0026deg;C\u003c/sub\u003e from the corresponding isothermal rheogram, it was evident that, except the 18:16 oleogels in mineral oil, independent of the type of oil, the oleogels that achieved the highest elasticity were those formulated with the molar fraction composition associated with the eutectic point (P\u0026thinsp;\u0026lt;\u0026thinsp;0.01; Table \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003eSM). The 18:16 oleogels in mineral oil formulated with 0.125 of C18 and 0.875 of C16 was the only system that achieved higher \u003cem\u003eG\u0026rsquo;\u003c/em\u003e\u003csub\u003e5\u0026deg;C\u003c/sub\u003e than the \u003cem\u003eG\u0026rsquo;\u003c/em\u003e\u003csub\u003e5\u0026deg;C\u003c/sub\u003e of the oleogel with MG composition associated with the eutectic point (Table \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e and Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003eB). However, the difference between the \u003cem\u003eG\u0026rsquo;\u003c/em\u003e\u003csub\u003e5\u0026deg;C\u003c/sub\u003e of this oleogel and the one of the oleogel formulated with MG composition associated with the eutectic point was not as large as the one observed by the same oleogels in vegetable oil (Table \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003eSM). In any case, the oleogels formulated with the molar fraction composition of the eutectic point achieved higher \u003cem\u003eG\u0026rsquo;\u003c/em\u003e\u003csub\u003e5\u0026deg;C\u003c/sub\u003e than the oleogels formulated at 1.0 molar fraction of C16, C18, and C22 (P\u0026thinsp;\u0026lt;\u0026thinsp;0.01; Table \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003eSM), and effect that was more evident with the vegetable oil oleogels (Table \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003eSM). As previously discussed, for each of the binary mixtures the corresponding MG composition at the eutectic point developed the least efficient aliphatic chains packing in the sub-\u0026alpha; phase. We considered that the microstructure developed by the aliphatic chain packing at the eutectic point favored the incorporation and retention of higher amounts of oil resulting in oleogels with higher elasticity. This in contrast with the elasticity achieved by the oleogels developed just by the individual MG and with binary MG composition different from the one associated with the eutectic point. Again, this except the \u003cem\u003eG\u0026rsquo;\u003c/em\u003e\u003csub\u003e5\u0026deg;C\u003c/sub\u003e achieved by the C18:C16 oleogel in mineral oil formulated with 0.125 of C18 and 0.875 of C16. The higher \u003cem\u003eG\u0026rsquo;\u003c/em\u003e\u003csub\u003e5\u0026deg;C\u003c/sub\u003e achieved by the vegetable oil oleogels in contrast with the mineral oil oleogels, had to be associated with the relative polarity effect on the MG crystal habit, particularly in the MG\u0026rsquo;s crystal size and shape. As already mentioned, in vegetable oil the MG crystallizes as small acicular crystals, while in the mineral oil the MG crystallizes as larger rod-shaped crystals [\u003cspan class=\"CitationRef\"\u003e24\u003c/span\u003e]. Thus, the crystal network microstructure developed by small crystals ought to provide a larger solid surface to liquid phase ratio than the microstructure developed by larger crystals. This could explain the higher \u003cem\u003eG\u0026rsquo;\u003c/em\u003e\u003csub\u003e5\u0026deg;C\u003c/sub\u003e achieved by the vegetable oleogels in comparison with the one achieved by the mineral oil oleogels. To explain the differential effect of the vegetable and the mineral oil on the rheological properties of oleogels developed by binary MG mixtures, we need to do microstructural and thermo-mechanical analysis, and also solid content and X ray measurements during oleogelation (i.e., cooling and isothermal conditions).\u003c/p\u003e\n\u003c/div\u003e"},{"header":"4. CONCLUSIONS","content":"\u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eTo our knowledge this is the first report that establishes the eutectic behavior of the sub-α phase in binary mixtures of saturated MG, and its relationship with the rheological properties of the MG oleogels. The phase diagrams obtained for the C18:C14, C18:16, and C18:C22 binary mixtures in the vegetable and mineral oil, showed that the eutectic behavior of the T\u0026deg;\u003csub\u003esub-α\u003c/sub\u003e was closely associated with the MG composition of the mixed Lα phase and with the aliphatic chains packing efficiency of the sub-α phase. We considered that at the MG molar composition corresponding to the eutectic point, the difference in length between the aliphatic chains in the mixed lamella resulted in a sub-α phase with the least efficient chain packing of that developed by any other MG molar fraction. It seemed that the aliphatic chain packing developed at the eutectic point by the binary mixtures of MG favored the incorporation and retention of higher amounts of oil, resulting in oleogels with higher elasticity. This in contrast with the elasticity achieved by the oleogels developed just by the individual MG and with binary MG composition different from the one associated with the eutectic point. However, although for each of the binary mixtures the corresponding MG composition at the eutectic point was the same in both oils (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e), the oleogels developed in the vegetable oil achieved higher elasticity than the mineral oil oleogels. Evidently, there is an effect of the type of oil (i.e., solvent relative polarity) on the rheological properties of the oleogels developed by binary MG mixtures, particularly with the MG composition associated with the eutectic point. We need to do additional studies involving microstructural and thermo-mechanical analysis, solid content and X ray measurements during the development of oleogels by binary MG mixtures using solvents of different polarity. This is particularly relevant for the cosmetic industry, where binary mixtures of MG could be used in the development of oleogels formulated using medium-chain triglycerides alone or in combination with other organic solvents of higher polarity like glycerol, 1,3-butanediol, 1,3-propanediol, 1, 6-hexanediol, 2-butoxyethanol or ester like 1-Methoxy-2-propanol acetate.\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e \u003ch2\u003eCONFLICT OF INTEREST\u003c/h2\u003e \u003cp\u003eThe authors declare that they have no conflict of interest.\u003c/p\u003e \u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eM. E., Char\u0026oacute;-Alvarado is currently a Ph. D. student, and these results are part of her thesis research. She was closely involved in the DSC and rheology measurements. M. A. Char\u0026oacute;-Alonso was involved in data collection and along with M. E., Char\u0026oacute;-Alvarado established the experimental conditions. J. F. Toro-Vazquez conception and design of the study, project and research group leader, also acting as M. E., Char\u0026oacute; Alvarado's thesis advisor. The first draft of the manuscript was written by J. F. Toro-Vazquez and all authors contributed and commented on further versions of the manuscript. All authors read and approved the final manuscript.\u003c/p\u003e\u003ch2\u003eAcknowledgments\u003c/h2\u003e \u003cp\u003eThe present research was supported by Consejo Nacional de Ciencia y Tecnolog\u0026iacute;a (CONACYT) through the grant CB-280981-2018. M. E., Char\u0026oacute; Alvarado greatly appreciates the scholarship provided by CONACYT to conclude her Ph.D. program.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eM.E. Morales, V. Gallardo, B. Clar\u0026eacute;s, M.B. Garc\u0026iacute;a, M.A. Ruiz, Int. J. Cosmet. Sci. 60 (6), 627 (2009)\u003c/li\u003e\n \u003cli\u003eD.S. Morrison, J. Schmidt, R. Paulli, J. Appl. Cosmetol. \u0026nbsp;14, 111 (1996)\u003c/li\u003e\n \u003cli\u003eZ.\u0026nbsp;Wang,\u0026nbsp;J.\u0026nbsp;Chandrapala,\u0026nbsp;T.\u0026nbsp;Truong, A.\u0026nbsp;Farahnaky, Food Sci. Nutr.\u0026nbsp;63(23),\u0026nbsp;6069 (2023)\u003c/li\u003e\n \u003cli\u003eF. C. S. C\u0026eacute;sar, P. M. B. G. Maia Campos, Int. J. Cosmet.\u0026nbsp;Sci. 42, 494 (2020)\u003c/li\u003e\n \u003cli\u003eJ. F. Toro-Vazquez, J. A. Morales-Rueda, A. Torres-Mart\u0026iacute;nez, M. A. Charó-Alonso, V. A. \u0026nbsp;Mallia, R. G. Weiss, Lagmuir 29(25), 7642 (2013)\u003c/li\u003e\n \u003cli\u003eA. L\u0026oacute;pez-Mart\u0026iacute;nez., J.A. Morales-Rueda, E. Dibildox-Alvarado, M.A. Char\u0026oacute;-Alonso, A.G. Marangoni, J.F. Toro-Vazquez,\u0026nbsp;Food Res. Int. 64, 946 (2014)\u003c/li\u003e\n \u003cli\u003eE. S. Lutton, J. of the Am. Oil Chem. Soc. 48(12), 778 (1971)\u003c/li\u003e\n \u003cli\u003eM. Char\u0026oacute;-Alvarado, M. Charo, A. De la Pe\u0026ntilde;a Gil, J. Toro-Vazquez, Food Biophys.\u0026nbsp;18(4), 1 (2023).\u003c/li\u003e\n \u003cli\u003eA. L\u0026oacute;pez-Mart\u0026iacute;nez, M.A. Char\u0026oacute;-Alonso, A. G. Marangoni, J.F. Toro-Vazquez, Food Res. Int. 72, 37 (2015)\u003c/li\u003e\n \u003cli\u003eD. Cholakova, N. Denkov, (2019). Adv. in colloid and intf. Sci. 269, 7 (2019)\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eD. Cholakova, K. Tsvetkova, S. Tcholakova, N. Denkov, Colloids Surf. A Physicochem. Eng. Asp. 634, 127926 (2022)\u003c/li\u003e\n \u003cli\u003eJ. F. Toro-Vazquez, J. D. P\u0026eacute;rez-Mart\u0026iacute;nez in Molecular Gels: Structure and Dynamics, ed. by R.G. Weiss\u0026nbsp;(The Royal Society of Chemistry, 2018), pp. 57\u0026ndash;87\u003c/li\u003e\n \u003cli\u003eS. Hasnain, Energy Conv. Mgmt. 39, 1139 (1998)\u003c/li\u003e\n \u003cli\u003eK. Huizhen, Appl. Therm. Engg. 113, 1319 (2017)\u003c/li\u003e\n \u003cli\u003eP. Zhao, Q. Yue, H. He, B. Gao, Y. Wang, Q. Li, Appl. Energy 115, 483 (2014)\u003c/li\u003e\n \u003cli\u003eU. Gala, H. Pham, H. Chauman, J. Develop. Drugs 2(3), 130 (2013)\u003c/li\u003e\n \u003cli\u003eI. Balakrishnan, N. Jawahar, V. Senthil, D. Debosmita, Int. J. Res. Pharm. Sci. \u0026nbsp;11(3), 3017 (2020)\u003c/li\u003e\n \u003cli\u003eJ. Tang, R. Daiyan, M.B. Ghasemian,\u0026nbsp;Nat. Commun.\u0026nbsp;10, 4645 (2019)\u003c/li\u003e\n \u003cli\u003eT. Malkin, M.R.J. Shurbagy. J. Chem. Soc. 0, 1628 (1936)\u003c/li\u003e\n \u003cli\u003eC. H. Chen, E. M. Terentjev, in Edible Oleogels: Structure and Health Implications, ed. by A.G. Marangoni, N. Garti (Elsevier, 2011), pp. 173\u0026ndash;201\u003c/li\u003e\n \u003cli\u003eC. H. Chen, I. Van Damme, E. M. Terentjev, Soft Matter 5(2), 432 (2009)\u003c/li\u003e\n \u003cli\u003eC. H. Chen, E. M. Terentjev, Langmuir 25(12), 6717 (2009)\u003c/li\u003e\n \u003cli\u003eA, Pizzirusso, F. Peyronel, E. D. Co, A. G. Marangoni, G. Milano, J. of the Am. Oil Chem. Soc,\u0026nbsp;140(39), 12405 (2018)\u003c/li\u003e\n \u003cli\u003eM. Aguilar-Z\u0026aacute;rate, A. De la Pe\u0026ntilde;a-Gil, F.M. \u0026Aacute;lvarez-Mitre, M.A. Char\u0026oacute;-Alonso, J.F. Toro-Vazquez. Food Biohys. 14, 326 (2019)\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"food-biophysics","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"Learn more about [Food Biophysics](https://www.springer.com/journal/11483)","snPcode":"11483","submissionUrl":"https://submission.nature.com/new-submission/11483/3","title":"Food Biophysics","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Saturated Monoglycerides, Phase Diagrams, Oleogels rheology","lastPublishedDoi":"10.21203/rs.3.rs-3928380/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-3928380/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"Phase diagrams of binary mixtures of 1-stearoyl glycerol (C18) with 1-myristoyl glycerol (C14), 1-palmitoyl glycerol (C16) or 1-monobehenin glycerol (C22) in vegetable and mineral oil were obtained using different molar fractions of the monoglycerides (MGs) keeping the MG concentration constant (8% wt/wt). We observed that, independent of the MG mixture (C18:C14, C18:C16, C18:C22) and the type of oil, the MGs developed a mixed La phase with a transition temperature practically independent of the C18 molar fraction. In contrast, the transition temperature for the sub-α phase showed a eutectic point that, for the same MG mixture, occurred in both oils at the same MG molar fraction. At the MG molar composition corresponding to the eutectic point, the difference in length between the aliphatic chains in the mixed lamella resulted in a sub-α phase with the least efficient chain packing of that developed by any other MG molar fraction. Independent of the MG mixture and the type of oil, the oleogels developed by cooling (80°C to 5°C) vegetable and mineral oil MG solutions followed by 180 min at 5°C achieved the highest elasticity (G’5°C) at the MG molar fraction composition associated with the eutectic point. Tentatively the least efficient aliphatic chains packing developed by the sub-α phase at the eutectic point, favored the incorporation and retention of higher amounts of oil. Thus, for a particular MG binary mixture, the oleogels at the eutectic point had the highest G’5°C in comparison with the G’5°C of oleogels formulated at any other MG proportion.","manuscriptTitle":"Phase Diagrams of Binary Mixtures of Saturated Monoglycerides in Vegetable and Mineral Oil and Their Impact in the Oleogels Rheology","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-02-06 11:30:44","doi":"10.21203/rs.3.rs-3928380/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"editorInvitedReview","content":"","date":"2024-03-05T15:51:53+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"3cf708d8-32c2-4424-8a11-6a3ea80a8b24","date":"2024-02-07T13:13:56+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"ec5973d6-3921-495d-8a4b-f03f9c48ec4f","date":"2024-02-05T14:33:32+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-02-05T14:25:01+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2024-02-05T01:12:08+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-02-05T01:12:08+00:00","index":"","fulltext":""},{"type":"submitted","content":"Food Biophysics","date":"2024-02-04T17:57:00+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"food-biophysics","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"Learn more about [Food Biophysics](https://www.springer.com/journal/11483)","snPcode":"11483","submissionUrl":"https://submission.nature.com/new-submission/11483/3","title":"Food Biophysics","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"52c36d16-44d5-49f1-81ad-f9ee3254f7ab","owner":[],"postedDate":"February 6th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2024-05-17T13:37:27+00:00","versionOfRecord":[],"versionCreatedAt":"2024-02-06 11:30:44","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-3928380","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-3928380","identity":"rs-3928380","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}