Properties of Oils and Hydrolysates Obtained from Tilapia (Oreochromis niloticus) By- Products Using Pressurized Fluid Technologies

Properties of Oils and Hydrolysates Obtained from Tilapia (Oreochromis niloticus) By- Products Using Pressurized Fluid Technologies | 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 Properties of Oils and Hydrolysates Obtained from Tilapia (Oreochromis niloticus) By- Products Using Pressurized Fluid Technologies Achamyelesh Duresa Duresa Seboka, Sisay Getachew Deressa This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9063071/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract In the fisheries industry, the consumption of residue and fish waste allows effective uses of the potential fish wastes as food additives, such as omega-3 fatty acids. Oil extraction from tilapia wastes and by-products were carried out by supercritical carbon dioxide (SC-CO 2 ) at 45 °C, 250 bar, for 3 h and n -hexane at 45 °C, 250 rpm, for 16 h. Hydrolysis of de-oiled tilapia residues was done by subcritical water at 160 °C and 190 °C. The overall oil yield obtained through SC-CO 2 was 34.3% ± 1.12% and through n -hexane was 63.5% ±0. 69%. Tilapia by-products were observed to have a higher proportion of total saturated fatty acids (SFAs) than monounsaturated fatty acids (MUFAs) and polyunsaturated fatty acids (PUFAs). The acid content of SC-CO 2 for the skin, head and viscera was 5.46 ± 0.25, 3.35 ± 0.28, and 7.19 ± 1.06 mg KOH/g, respectively, and the peroxide values (PVs) were 1.77 ± 0.43, 1.34 ± 0.46, and 4.48 ± 0.17 meq/kg, respectively. The free fatty acid (FFA) obtained via SC-CO 2 yields 3.62% ± 0.10% (skin), 1.79% ± 0.09% (head), and 4.29% ± 0.41% (viscera), and that via n -hexane yields 3.19% ± 0.35% (skin), 1.69% ± 0.02% (head), and 4.44% ± 0.55% (viscera) within a reasonable value range 1%–7%. Hydrolysate values ranged from 2.04% ± 0.01% to 7.44% ± 0.01% of samples. The maximum and minimum values of protein were 40.42 ± 0.79 and 31.28 ± 0.92 mg BSA/g and that of total sugar were 30.06 ± 4.07 and 28.51 ± 0.83 mg Glu/g, respectively. SC-CO 2 and n -hexane are the favored techniques in the valorization of tilapia waste containing substantial bioactive compounds that are essential for human and animal health. Biomass valorization pressurized liquid tilapia waste polyunsaturated fatty acids hydrolysis Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted 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-9063071","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":602546051,"identity":"31088260-9d04-44d1-a3be-7cd5e5bf57d6","order_by":0,"name":"Achamyelesh Duresa Duresa Seboka","email":"","orcid":"","institution":"Ministry of Agriculture","correspondingAuthor":false,"prefix":"","firstName":"Achamyelesh","middleName":"Duresa Duresa","lastName":"Seboka","suffix":""},{"id":602546052,"identity":"ea42c5c6-8ce0-4c3e-ba19-6681e0576f57","order_by":1,"name":"Sisay Getachew Deressa","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA6ElEQVRIie3PMQrCMBSA4YRA6vDQNYK0VygERNDDtEundHcQUQpx09lbODkrwUweoKNQcBCEiuCoNk5ONW6C+YdHAvlIgpDL9YsRMqnmAKiXbaoF61gQbEjiN0FHhoDFNS+iuM9EaLafSTDD0wKGJJZMXE/5qAfIU7tVHQkVzjjsaSzhvO4LXT0MkiSvJQTL9lJCLL10zQWtCINuLQkyQ+4slkgcubhbEKSwZJdJyGlDkCKVFsT8JSx15FPQXZLOGdBPfwkWanuIRg8IZllxFbex3/KUrn/YW5S9pu1xEym/Oe1yuVz/0xOgtkNvka58NgAAAABJRU5ErkJggg==","orcid":"","institution":"Ministry of Agriculture","correspondingAuthor":true,"prefix":"","firstName":"Sisay","middleName":"Getachew","lastName":"Deressa","suffix":""}],"badges":[],"createdAt":"2026-03-08 09:08:15","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9063071/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9063071/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":104779709,"identity":"2dd90708-5d66-4d9d-9fd5-0925ee6f138d","added_by":"auto","created_at":"2026-03-17 07:45:02","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":670446,"visible":true,"origin":"","legend":"","description":"","filename":"Manuscriptspringer.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9063071/v1_covered_6caa09c4-1edf-4b8e-a8d8-a5a290825c57.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Properties of Oils and Hydrolysates Obtained from Tilapia (Oreochromis niloticus) By- Products Using Pressurized Fluid Technologies","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Biomass valorization, pressurized liquid, tilapia waste, polyunsaturated fatty acids, hydrolysis","lastPublishedDoi":"10.21203/rs.3.rs-9063071/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9063071/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eIn the fisheries industry, the consumption of residue and fish waste allows effective uses of the potential fish wastes as food additives, such as omega-3 fatty acids. Oil extraction from tilapia wastes and by-products were carried out by supercritical carbon dioxide (SC-CO\u003csub\u003e2\u003c/sub\u003e) at 45 °C, 250 bar, for 3 h and \u003cem\u003en\u003c/em\u003e-hexane at 45 °C, 250 rpm, for 16 h. Hydrolysis of de-oiled tilapia residues was done by subcritical water at 160 °C and 190 °C. The overall oil yield obtained through SC-CO\u003csub\u003e2\u003c/sub\u003e was 34.3% ± 1.12% and through \u003cem\u003en\u003c/em\u003e-hexane was 63.5% ±0. 69%. Tilapia by-products were observed to have a higher proportion of total saturated fatty acids (SFAs) than monounsaturated fatty acids (MUFAs) and polyunsaturated fatty acids (PUFAs). The acid content of SC-CO\u003csub\u003e2\u003c/sub\u003e for the skin, head and viscera was 5.46 ± 0.25, 3.35 ± 0.28, and 7.19 ± 1.06 mg KOH/g, respectively, and the peroxide values (PVs) were 1.77 ± 0.43, 1.34 ± 0.46, and 4.48 ± 0.17 meq/kg, respectively. The free fatty acid (FFA) obtained via SC-CO\u003csub\u003e2\u003c/sub\u003e yields 3.62% ± 0.10% (skin), 1.79% ± 0.09% (head), and 4.29% ± 0.41% (viscera), and that via \u003cem\u003en\u003c/em\u003e-hexane yields 3.19% ± 0.35% (skin), 1.69% ± 0.02% (head), and 4.44% ± 0.55% (viscera) within a reasonable value range 1%–7%. Hydrolysate values ranged from 2.04% ± 0.01% to 7.44% ± 0.01% of samples. The maximum and minimum values of protein were 40.42 ± 0.79 and 31.28 ± 0.92 mg BSA/g and that of total sugar were 30.06 ± 4.07 and 28.51 ± 0.83 mg Glu/g, respectively. SC-CO\u003csub\u003e2\u003c/sub\u003e and \u003cem\u003en\u003c/em\u003e-hexane are the favored techniques in the valorization of tilapia waste containing substantial bioactive compounds that are essential for human and animal health.\u003c/p\u003e","manuscriptTitle":"Properties of Oils and Hydrolysates Obtained from Tilapia (Oreochromis niloticus) By- Products Using Pressurized Fluid Technologies","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-03-10 09:29:51","doi":"10.21203/rs.3.rs-9063071/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"2bdbd2be-d5ac-4d73-abfa-562f2c7da40c","owner":[],"postedDate":"March 10th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-03-11T14:11:06+00:00","versionOfRecord":[],"versionCreatedAt":"2026-03-10 09:29:51","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9063071","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9063071","identity":"rs-9063071","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}