Use of Soybean Oil Deodorizer Distillate as Raw Material for Synthesis of Ethyl Esters and Xylose Esters Using a Hydroesterification Strategy

The enzymatic production of fatty acid ethyl esters (FAEEs) and xylose fatty acid esters (XFAEs) from soybean oil deodorant distillate (SODD) has been investigated using a hydroesterification strategy. SODD was hydrolyzed and the glycerol-free fraction were esterified with xylose or ethanol. Free lipase from Pseudomonas fluorescens (PFL) yielded 84 wt.% of free fatty acids (FFAs) (around 15% FFAs remained as glycerides) after 48 h using a SODD/water mass ratio of 1:4 and an enzyme load of 5 wt.% (considering the oil mass). In the synthesis of FAEEs, free Eversa Transform transformed approximately 82% of the FFAs into FAEEs after 48 h using an ethanol:FFAs molar ratio of 3.64:1 and an enzyme load of 8.36% (w/v). In the synthesis of XFAEs, lipase from Thermomyces lanuginosus (TLL-T2-150) and PFL (IMMAPF-T2-150) commercially immobilized on Immobead T2-150 were used in the process. TLL-T2-150 gave lower xylose ester modification (80.20%) compared to IMMAPF-T2-150 (89.20%) after 24 h using an FFAs/xylose molar ratio of 5 in ethyl-methyl-ketone (xylose concentration of 7 mmol L-1) and enzyme load of 0.5% (w/v). However, it consumed more FFAs, suggesting a higher xylose esterification degree using TLL-T2-150. Using this biocatalyst, the final reaction mixture containing XFAEs showed adequate emulsifying properties.