Interfacial dilatational and emulsifying properties of ultrasound-treated pea protein.

In this study, the structural, interfacial, and emulsifying properties of high-intensity ultrasound (HUS)-treated pea protein isolate (PPI) were investigated. HUS at 50% amplitude and 57-60 W·cm for 5 min markedly improved protein solubility (by 132%), surface hydrophobicity (by 173%), and reduced particle size (by 52%). These physicochemical changes in PPI led to more rapid protein adsorption at the oil-water interface, improved emulsifying activity (by 18-27%) and capacity (by 11%), and enhanced emulsion physical stability. The multilayer nature, albeit less elastic, of the interfacial membrane formed by PPI when compared to control protein (PPI), based on dilatational testing, contributed to the above results. Moreover, PPI-stabilized emulsions exhibited a tendency of being less susceptible to lipid oxidation during storage. Thus, structure-modifying HUS may be a valuable processing technology for the manufacture of pea protein-based emulsion foods.