Interactions of OSA‐Modified Starch and Heat‐Treated Whey Protein Alter the Structural, Rheological, and In Vitro Digestibility Properties of Starch

ABSTRACT The effects of molecular interaction between heat‐treated whey protein (WPI) and octenyl succinic anhydride modified starch (OSAS) on the structural, rheological, digestibility, and release properties of WPI‐OSAS were investigated. Results revealed that the molecular interaction of WPI‐OSAS had a positive influence on the degree of substitution, rough surface, storage modulus, loss modulus, tan δ, resistant starch content, encapsulation efficiency of curcumin, and controlled release of curcumin in simulated gastrointestinal conditions, but there was a negative effect on R 1047/1022, equilibrium hydrolysis percentage, and kinetic constant. These effects were more evident in WPI‐OSAS with WPI heat treatment temperature at 90°C, caused by the stronger hydrophobic interaction between WPI and OSAS. The hydrophobic interaction of WPI‐OSAS improved the rheology, anti‐digestibility, encapsulation, and release properties of WPI‐OSAS, which enriched the application of WPI‐OSAS in functional foods.