Plant-derived insoluble protein aggregates: Formation mechanisms, influencing factors, solubilization, functional properties, and applications

Plant protein is a high-quality protein resource and has been widely used in various fields of the food industry. However, during food processing, especially thermal processing, enzymatic hydrolysis and enzymatic cross-linking, insoluble protein aggregates are inevitably formed. Hydrogen bonds, hydrophobic interactions and van der Waals forces are the main forces that maintain the structural stability of insoluble protein aggregates, and the structure of insoluble protein aggregates could be changed by physical, chemical and enzymatic hydrolysis treatments to improve their solubility or reduce the degree of formation. At present, due to the insufficient utilization of insoluble protein aggregates, they are often discarded or used as raw material for animal feed, resulting in a large waste of plant protein resources. This paper summarizes the formation mechanism, influencing factors, functional properties and applications of insoluble protein aggregates, which provides a theoretical basis for further research and expansion of insoluble protein aggregates in the food industry.