Effect of Amylose Content on the Structural and Physicochemical Properties of High‐Amylose Starch‐Whey Protein Isolate‐Lauric Acid Complexes

This study investigated the influence of amylose content on the structural and physicochemical properties of starch‐whey protein isolate (WPI) ‐lauric acid (LA) ternary complexes. Three wheat starches (NWS: 39.82% amylose, HWS1: 78.57% amylose, HWS2: 81.62% amylose) were used to investigate the morphology, short‐range ordering degree (OD), X‐ray diffraction (XRD), thermal properties, and starch digestibility of their complexes with WPI and LA. NWS showed A‐type crystallinity, whereas HWS1 and HWS2 exhibited B‐type crystallinity with lower relative crystallinity. The structural and functional properties of ternary complex showed systematic changes compared to their corresponding binary complexes and gelatinized starches. Specifically, higher amylose content reduced short‐range ordering degree (OD) and relative crystallinity of native starches while concurrently enhancing thermal stability, enthalpy change (ΔH), and resistance to enzymatic digestion. Morphological analysis revealed distinct particle restructuring, with FT‐IR spectroscopy identifying that increasing amylose content led to greater formation of starch‐WPI‐LA complexes. Notably, these starch‐WPI‐LA ternary complexes exhibited higher OD compared to starch‐LA binary complexes. These findings provide critical criteria for starch selection in functional food formulations.