Anthocyanin-loaded double Pickering emulsion stabilized by octenylsuccinate quinoa starch: Preparation, stability and in vitro gastrointestinal digestion

Abstract

In this study, anthocyanin-loaded water1-in-oil-in-water2 (W1/O/W2) double Pickering emulsions stabilized by octenylsuccinate quinoa starch (OSQS) were optimized, and their storage stability and in vitro gastrointestinal digestion were evaluated. Novel starch-based double emulsions as anthocyanin cargos were achieved at 2% (w/v of oil) of polyglycerol polyricinoleate concentration, the W1/O volume proportion of 3:7, 6% (w/v of total volume) of OSQS concentration, and the volume proportion of (W1/O): W2 = 6:4 and 5:5. CLSM results evidenced the formation of double Pickering emulsions, and the significant decreases in the encapsulation stability of anthocyanins were closely related to the increases in the droplet size induced by osmotic pressure. Less than 15% of anthocyanins in the double Pickering emulsions was released after incubated for 60 min under simulated stomach conditions; controlled-release of anthocyanins was observed during the 120 min of simulated intestinal digestion, consistent with starch hydrolysis data. These findings will be useful for designing starch-based double Pickering emulsion with intestinal-targeted delivery as a novel carrier of sensitive hydrophilic bioactive compounds.