Fabrication and characterization of glucono-δ-lactone-induced cold-set emulsion gels stabilized by a whey and pea protein mixture at various mixing ratios for the delivery of curcumin

In this study, glucono-δ-lactone-induced cold-set emulsion gels stabilized by whey protein (WPI) and pea protein (PPI) at various mass ratios were formulated, characterized, and applied. Compared with WPI-stabilized emulsion, zeta potential of emulsion decreased but droplet size, apparent viscosity, and modulus increased with increasing PPI. Differences in the properties of emulsions led to differences in the structure and properties of gels formed. Compared with emulsion gel formed by single PPI, the addition of WPI was found to improve the microstructure, water-holding capacity, rheological, and texture properties of emulsion gel, and the synergistic effect of WPI and PPI was observed at a mixing ratio of 75/25. In vitro digestion experiments revealed that all emulsion gels demonstrated comparable encapsulation, but adding PPI reduced stability and bio-accessibility, regardless of ratio. Data indicated that this method could produce a stable emulsion gel with properties modulated by adjusting the whey and pea protein ratio.