Effects of Treatment Methods on the Formation, Structure, and Functional Properties of Soy Protein Amyloid Fibrils

To investigate the effects of different treatment methods on soybean protein amyloid fibrils (SPAF), this study examined the effects of ultrasonication, cold plasma, heat, and NaCl treatment on the formation, structure, and functional properties of SPAF. SPAF structural analyses indicated that all treatments promoted SPAF assembly, with the order of effectiveness being: heat treatment > ultrasonication > cold plasma treatment > NaCl treatment. Regarding functional properties, the heat treatment group also demonstrated superior overall performance, including the highest solubility (88.15%), optimal emulsifying activity (79.63 m²/g) and foaming capacity (169.44%), and the highest thermal denaturation temperature (107.49 °C). Conversely, ultrasonication and cold plasma treatments, which generated shorter fibrils, offered moderate functional improvements. In contrast, NaCl treatment provided limited functional enhancement due to the formation of coarse aggregates. Consequently, heat treatment was identified as the most effective approach to promote SPAF formation and enhance functional properties. These findings provide a theoretical basis for the process optimization of SPAF in the food industry.