Physicochemical and digestion properties of fish oil and anthocyanins co-encapsulated W/O/W emulsion reinforced with alginate

W/O/W double emulsion systems offer the ability to co-deliver water-soluble and oil-soluble bioactives, making them a promising choice for multifunctional delivery applications. This study focused on the development of a whey protein isolate-based W/O/W emulsion encapsulating fish oil and anthocyanins, with the addition of sodium alginate (SA) into the external aqueous phase. The physicochemical properties, emulsion stability, anthocyanins encapsulation efficiency (EE), and anthocyanins release during simulated gastrointestinal digestion were studied. The results indicated that the physical stability of W/O/W emulsions improved with increasing SA, attributed to the higher viscosity and the protective coating of SA on the WPI-stabilized interface. However, the EE of anthocyanins in SA-reinforced W/O/W emulsions was found to be lower. Excessive SA concentration, such as 1.0%, was observed to be unfavorable to maintaining the internal W1/O interface integrity. Overall, the double emulsion structure effectively regulated the release of anthocyanins throughout the digestion process. The study concluded that W/O/W emulsions containing 0.75% SA achieved optimal stability and controlled-release characteristics. These findings offer valuable insights into fabricating double emulsions for multifunctional delivery purposes, showcasing their potential applications in the food and pharmaceutical industries.