Flavor enhancement of soy protein isolate hydrolysates through the Maillard reaction and identification of saltiness-enhancing peptides

This work enhances the overall flavor of soy protein isolate hydrolysates through the Maillard reaction. Maillard reaction dynamics were monitored using ultraviolet spectroscopy, analysis of free amino acids, and GC-IMS. The reaction products significantly enhanced saltiness and identified two peptides, DDFF and DFGKF, that showed significant saltiness-enhancing properties, with enhancement thresholds of 0.23 and 0.37 mmol/L, respectively, as determined by sensory evaluation and the electronic tongue. Molecular docking revealed that key amino acids in the calcium-sensing receptor (CaSR), including Ser302, Ser303, Thr411, and Arg66, were responsible for interacting with the peptides. Molecular dynamics simulations confirmed the stability of these interactions. These findings provide theoretical support for the extraction and application of salinity-enhancing peptides.