Effects of Ph and Temperature on the Properties of Acid-Induced Soy Protein Isolate Gel

Abstract

The goals of this study were to investigate the effect of preheating conditions on the formation of thermal aggregates of soy isolate protein (SPI) and to characterize the textural properties and microstructure of acid-induced SPI gels. Characterization of the different gels showed that lower temperatures and pH values favored protein aggregation and the formation of larger aggregates, while higher temperatures and pH values led to a lower degree of aggregation and the formation of smaller aggregates. These exposed groups facilitated protein-protein interactions during network assembly, resulting in denser and stronger gel networks. Notably, SPI subjected to higher temperatures and pH values exhibited greater binding capacity for water molecules, higher water holding capacity, and gel strength. Overall, the results showed that modification of preheating temperature and pH can control the formation state of SPI thermal aggregates, ultimately impacting the properties of SPI acid-induced gels.

Keywords: Acid-induced gel, SPI thermal aggregates, Temperature, pH values