Electrokinetic interaction and dynamic wetting behavior of soy protein/gum arabic coacervates as soft particles

In recent years, the growing demand for sustainable and clean-label health foods has made mild processing a key approach to obtaining less denatured and high-quality plant-based protein ingredients. This study compared soy protein isolate (SPI) obtained via salt extraction (S-SPI) with SPI obtained via the conventional alkali-solubilization and acid-precipitation method (A-SPI), to investigate the impact of protein aggregation structure on the formation of SPI/gum arabic (GA) complex coacervation. Native-PAGE and SDS-PAGE results revealed that mild extraction processes lead to the enrichment of glycinin in SPI. The electrokinetic interactions of S-SPI/GA coacervates were analyzed using soft particle theory, linking the charged properties of biopolymers to their complex structures. Dynamic wetting behavior results showed that the low interfacial tension of S-SPI/GA coacervates facilitated wetting at the oil–water interface and the formation of a continuous layer. This study proposed a novel approach to developing low-denaturation, natural plant proteins and provided new insights into the formation mechanisms of plant protein-based complex coacervates.