Bovine serum albumin-EGCG particles increase high internal phase pickering emulsions stability: The leading role of EGCG concentrations

Bovine serum albumin (BSA)-epigallocatechin-3-gallate (EGCG) have been widely studied; however, the effects of EGCG concentration on the properties of these complexes and their influence on the stability of high-internal-phase Pickering emulsions (HIPPEs) remain limited. This study aims to reveal the interactions between BSA and varying concentrations of EGCG and the application of BSA-EGCG complexes for creating stable emulsions. As the concentration of EGCG decreases from 0.3% to 0.1%, the β-sheet content significantly increased and the β-turn content significantly decreased, resulting in smaller sizes and zeta potentials of 50 μm and −58.7 mV, respectively, at a 0.1% EGCG concentration. This change enhances the ability of BSA-EGCG to adsorb at the oil-water interface, effectively lowering interfacial tension and increasing the emulsion viscosity. Moreover, the interactions between BSA and EGCG markedly improved pH stability, ionic stability, thermal stability, centrifugal stability, and freeze-thaw stability of emulsions. These findings highlight the valuable role of EGCG levels on BSA-EGCG interactions and formed HIPPEs, suggesting their promising applications in the food and pharmaceutical industries. • Bovine serum albumin (BSA) binds to EGCG through hydrophobic and hydrogen interactions. • EGCG altered the secondary structure of BSA. • Smallest emulsion size, zeta potential and interfacial tension were observed at 0.1% EGCG. • Increasing EGCG from 0.1% to 0.3% decrease emulsion viscosity. • BSA-EGCG complex significantly enhanced the stability of HIPPEs.