Preparation of protein-polyphenol-polysaccharide ternary complexes to regulate the interfacial structure of emulsions: Interfacial behavior and emulsion stability

This study investigated the effect of protein-polyphenol-polysaccharide ternary complexes prepared from polysaccharides with different charges on emulsion stability. Sodium alginate (ALG), chitosan hydrochloride (CHC) and oat β-glucan (OG) were used as representational polysaccharides. The interfacial rheology showed that CHC increased the adsorption rate of WPI-rutin complexes at the oil-water interface, while ALG and OG reduced the adsorption rate. Furthermore, WPI-Rutin-CHC complexes effectively reduced the interfacial tension from 11.16 mN/m to 9.41 mN/m. Compared with other ternary complexes, the oil-water interface layer composed of WPI-Rutin-CHC complexes had the highest interfacial viscoelasticity and mechanical strength. Moreover, the emulsion prepared by WPI-Rutin-CHC complexes had the lowest instability index (0.17) and the smallest droplet size (660 nm), indicating the highest stability among all the emulsions. The microstructure results indicated that the thick interfacial layer was observed in WPI-Rutin-CHC emulsion, while thin interfacial layers were found in other emulsions. These results revealed the stability mechanism of emulsions prepared by ternary complexes and provided guidance for the preparation of stable emulsions.