Modification of Foaming Properties of Commercial Soy Protein Isolates and Concentrates by Heat Treatments

Abstract

AbstractCommercial soy protein isolates (SPIs; China 980A, China 880, ISP 974 and ADM 974) and soy protein concentrates (SPCs; SPC 700 and ARCON S) were used for comparing the effects of heat treatment (55C and 85C for 10–30 min) on the surface tension, surface hydrophobicity, viscosity, solubility at pH 3–8 and foaming properties. The foam capacity was highly positively correlated with the surface hydrophobicity, but negatively related to the surface tension, liquid percentage and foam maximum density. Heating commercial SPIs and SPCs improved the foam capacity, changed the surface hydrophobicity, solubility, foam maximum density and foam stability, and decreased the surface tension and viscosity. The heating temperatures had a greater influence on protein properties than did the heating time. Among soy protein products, heat‐modified China 980A had the best foam capacity and foam stability.Practical ApplicationsSimple heating treatments improved foaming properties of commercial soy products with low level of surface tension and high level of surface hydrophobicity and solubility. In particular, heating improved surface tension, foaming capacity, liquid percentage, foam maximum density and not damaged foaming stability in most of samples. These results indicate that a relatively inexpensive, high quality foaming properties was obtained by the action of heating process that benefits the application of using commercial soy proteins as foaming agents in aerated food systems. Therefore, the foaming properties of heated soy proteins were dramatically different, showing great potential for improving tailor‐made proteins for various applications.