Stability, microstructure, and digestibility of whey protein isolate – Tremella fuciformis polysaccharide complexes

Abstract

Abstract Manufacturing of protein-enriched beverages is an interesting field which has attracted a lot of attention from the research community. In this study, polysaccharides extracted from a mushroom (Tremella fuciformis) were used to enhance the stability of 5% whey protein isolate (WPI) solution for enriched beverage development with excellent results. Rheological studies showed that the T. fuciformis polysaccharides (TP) enhanced WPI solution exhibited characteristics of pseudoplastic fluid. Microstructure studies showed that the WPI–TP complexes formed more orderly structures than that of the two monomers. A new limited proteolysis-coupled mass spectrometry technique was utilized to characterize the in vitro digestibility of WPI-TP complexes: the rate of digestion of WPI-TP was shown to be significantly lower than that of WPI, which would reduce gastric emptying time and increase satiety. In addition, the degree of digestibility of each protein and the potential binding regions of TP-WPI were also revealed by this new technique.