Role of Plant Proteins in Altering the Physicochemical Characteristics of Wheat Starch–Lauric Acid System

The study explored the impact of cashew (CP), quinoa (QP), and flaxseed proteins (FP) on the properties and structure of wheat starch-lauric acid (WS-LA) system using rapid viscosity analyzer (RVA), rheology, texture analysis, thermogravimetric analysis (TGA), confocal laser scanning microscopy (CLSM), scanning electron microscopy (SEM) and X-ray diffraction (XRD). The study found that LA promoted the formation of V-type WS-LA complexes, enhanced the short-range order and relative crystallinity of WS, and disrupted its gel network, leading to a decrease in tan δ of WS. Proteins (CP, QP, and FP) further decreased tan δ and increased the cooled peak viscosity of WS-LA system due to the formation of WS-LA-protein complexes with high relative crystallinity. Proteins prompted WS-LA gels to form a denser, more compact three-dimensional network that physically entrapped WS granules within a continuous lipid-protein matrix, which reduced starch digestibility in vitro compared to WS-LA system. This study offered guidance for incorporating protein into starch-based foods with reduced digestibility.