Study on the fabrication and in vitro digestion behavior of curcumin-loaded emulsions stabilized by succinylated whey protein hydrolysates

In this study, the succinic anhydride (SA) modified whey protein isolate (WPI) and whey protein hydrolysates (WPH) were prepared and characterized as novel emulsifiers. After the succinylation, the solubility, emulsibility, and water/oil binding capacity of WPI/WPH were improved. Emulsions with modified and unmodified WPI/WPH were prepared and characterized on rheological property, particle sizes, and droplet distribution using rheometer, zeta-sizer and confocal laser scanning microscopy. A simulated digestion system was utilized to monitor the gastrointestinal fate of emulsions and the bioaccessibility of curcumin loaded in emulsions. The final digestion extents of WPIE-10 and WPHE-10 (emulsions stabilized by modified WPI/WPH with 10% SA addition) were lower than those of WPIE-0 and WPHE-0 (emulsions stabilized by unmodified WPI/WPH). The order of curcumin bioaccessibility was WPIE-10 (79.64%)approximate to WPHE-10 (86.75%) > WPIE-0 (64.23%)approximate to WPHE-0 (60.62%). Our study provided valuable information about novel emulsifiers stabilizing delivery system to improve curcumin bioaccessibility.