Abstract:In this study, the O/W emulsions have been generated by using β-conglycinin(7S) and glycinin(11S) as emulsifiers with adding Epigallocatechin gallate (EGCG). Three-dimensional fluorescence spectrum, thermal stability,particle size and ζ-potential of soy protein-EGCG complex, droplet size, chromatic aberration, droplet morphology and interfacial protein adsorption of the emulsion were determined in order to investigate the effects of EGCG interaction with 7S/11S proteins on emulsion stability. The results showed that EGCG decreased the fluorescence intensity of 7S/11S protein, resulting in an unfolding in soy protein tertiary structure and reducing thermal stability. EGCG caused the cross-linking of 7S/11S protein, increasing the particle size of its protein particles, and enhancing its ζ-potential to a certain extent. 11S protein was more sensitive to the above changes, suggesting that the interaction between 11S protein and EGCG was stronger than that of 7S protein. The addition of EGCG increased the a and b values of both protein emulsions, and significantly reduced the droplet size. When EGCG concentration was up to 0.02%, d4,3 of 7S/11S protein emulsion was the smallest, but 11S protein emulsion droplets still existed in the form of large aggregates. EGCG significantly improved the storage stratification of 7S protein emulsion, but had no significant effect on 11S protein emulsion. In addition, EGCG had no effect on the overall subunit distribution of 7S/11S protein emulsion interface proteins.