Binary complexes of whey protein fibers/isolates and fish gelatins for emulsion stabilization

In this work, fish gelatins (FG) were mixed with whey protein fibers (WPF) and native whey protein isolates (WPI) under acidic and neutral pH conditions, respectively. The objective of this study was to explore how binary protein FG and WPI/WPF cooperated to stabilize oil-in-water emulsion systems. The emulsion, stabilized solely by WPI, flocculated and coalesced easily at both pH values. Fibrillation could increase surface hydrophobicity and interfacial activity at pH 7, resulting in improved creaming stability of emulsions compared to natural WPI. However, the improvement in creaming stability was limited. When FG cooperated with WPI and WPF, FG could contribute to the formation of a 3D network to enhance the physical stability of emulsions. In addition, WPI and WPF could contribute to surface activity in binary proteins. FG-WPF exhibited better compatibility than FG-WPI and a faster gelation rate, superior viscoelastic properties, and greater deformation resistance. In addition, WPF may help to improve the gelation behavior of FG-WPF at pH 3. This research introduced a new binary protein system consisting of whey protein fibers and fish gelatins that might be used as promising emulsifiers and stabilizers in emulsion systems.