Gelatin-crosslinked millard reaction products of sodium caseinate/ maltodextrin enhances the encapsulation efficiency and stability of krill oil microcapsules

The Maillard reaction is an effective way to enhance the properties of microcapsule wall materials. This study investigated the optimal ratio and physicochemical properties of Maillard reaction products from sodium caseinate (CAS) and maltodextrin (MD), as well as their crosslinked derivatives with gelatin (GEL). The application of Maillard reaction products (CAMD) as wall materials in the preparation of krill oil microcapsules (KOMs), raised the encapsulation efficiency (EE) of KOMs to 94.5 % compared with the physical mixture. The further addition of gelatin raised the EE to 96.9 %. The gelatin crosslinked Maillard reaction products (CAMEL) also exhibited superior antioxidative properties, and as wall materials enhanced the storage stability of KOMs, whose surface oil was 16.98 % over six months, only 71.16 % of that of the physical mixture. In vitro simulated release of KOMs demonstrated that CAMEL could reduce the release of free fatty acids (FFA) by 14.66 % compared to physical mixtures. These findings suggest that microencapsulation with CAMEL provides enhanced protection for krill oil, demonstrating significant potential for the practical application in the scale-up production.