Effect of protease species on structure, interfacial behavior, and foaming properties of limited enzyme hydrolysis products of soybean protein isolate and mung bean protein

Plant protein foams face limitations in foaming capacity (FC) despite their industrial potential. This study innovatively employed six distinct proteases (Trypsin, Alcalase, Papain, Neutrase, Compound proteinase, Flavourzyme) for limited enzymatic hydrolysis of soy protein isolate (SPI) and mung bean protein (MBP) to enhance their interfacial and foaming properties. Crucially, hydrolysis significantly reduced molecular weight and particle size, increased molecular flexibility, and lowered surface tension for both proteins. These structural modifications facilitated rapid adsorption and rearrangement at the air-water interface. Consequently, all enzymatic treatments markedly enhanced FC (Trypsin maximized SPI FC to 167.33 %, Flavourzyme maximized MBP FC to 190.67 %) without compromising foaming stability. This systematic investigation establishes a clear structure-function relationship between enzymatic modification, interfacial activity, and enhanced foaming performance. It provides critical insights for selecting optimal proteases to tailor SPI and MBP functionality, significantly broadening their application in foam-based food products.