Studies on the Properties and Stability Mechanism of Double Emulsion Gels Prepared by Heat-Induced Aggregates of Egg White Protein-Oligosaccharides Glycosylation Products

Multiple emulsions can dissolve some substances with different properties, such as hydrophilicity and lipophilicity, into different phases. They play an important role in protection, controlled release and targeted release of the encapsulated substances. However, it’s poor stability has always been one of the main problems restricting its application in the food industry. For this reason, a heat-induced aggregate (HIA) of Maillard graft product of isomalto-oligosaccharides (IMO), as well as egg white protein (EWP), was used as hydrophilic emulsifier to improve the stability of W1/O/W2 emulsions. Moreover, gelatin was added into the internal aqueous phase (W1) to construct W1/O/W2 emulsion-gels system. The encapsulation efficiency of HIA-stabilized W1/O/W2 emulsions remained nearly unaltered, dropping by only 0.86%, significantly outperforming the conjugates and physical mixture of IMO and EWP in terms of encapsulation stability. The emulsion-gels system was constructed by adding 5% gelatin in the W1, and had the highest EE% and good salt and heat stability after 30 days of storage. This experiment provides guidance for improving the stability of W1/O/W2 emulsions system and its application in the package delivery of functional substances in the food field.