Emulsion-templated oleogel based on an OSA starch-gelatin-tannic acid ternary complex for algal oil delivery.

Abstract

In this study, ternary complexes composed of octenyl succinate acetylated starch (OS), gelatin (GE), and tannic acid (TA) were used to fabricate oleogels via an emulsion-template method combined with freeze-drying for algal oil delivery. The results indicated that electrostatic interactions and hydrogen bonding drove the formation of the ternary complex, resulting in a stronger oleogel network and improved viscoelastic properties and storage stability. Under accelerated oxidation, OS-GE-TA oleogels exhibited significantly (p < 0.05) lower peroxide values than OS oleogels, with reductions of 9.55-12.87 meq/kg oil, and effectively inhibited fishy odor-related volatiles. In vitro digestion results showed that the free fatty acid (FFA) release of OS-GE-TA0.4 and OS-GE-TA0.8 oleogels reached 71.17% and 80.42%, respectively, both significantly (p < 0.05) higher than algal oil (64.28%), indicating enhanced lipid digestion and DHA release under simulated gastrointestinal conditions. Overall, the novel oleogels developed in this study have considerable potential for DHA delivery.