Fabrication of oil-in-water high internal phase emulsions with enhanced antioxidative properties by modified starch/polyphenol mixtures: Effect of EGCG concentration, NaCl concentration, and temperature.

In this study, oil-in-water (O/W) high internal phase emulsions (HIPEs) with enhanced antioxidative properties stabilized by octenyl succinic anhydride modified starch (OSAS)/(-)-Epigallocatechin-3-gallate (EGCG) mixtures were prepared. The influence of EGCG concentration (0-0.2 %, w/v), NaCl concentration (0-400 mmol/L), and temperature (25-90 °C) on the stability of the HIPEs was evaluated. The formation of O/W HIPEs, and OSAS/EGCG mixtures formed a thicker barrier on the surface of the oil droplets was confirmed using confocal laser scanning microscopy (CLSM) and cryo-scanning electron microscopy (Cro-SEM), respectively. The results indicated the HIPEs stabilized by OSAS/EGCG mixtures exhibited good environmental stability. All HIPEs displayed excellent antioxidant properties. As the concentration of EGCG in the OSAS/EGCG mixtures was increased from 0 to 0.2 % (w/v), the lipid hydroperoxide (LH) content was reduced from 534.89 mmol/kg oil to 453.77 mmol/kg oil, and malondialdehyde (MDA) content was reduced from 10.15 mmol/kg oil to 6.07 mmol/kg oil. Combined with the effect of NaCl, the oxidative stability was improved further. This study provided a new formulation of food-grade O/W HIPEs with strong antioxidant properties could be a potential solid fat substitute for future foods.