Study on the Macro- and Micro-Stability of Protein-Based Pickering Emulsions and Their Food Applications

Existing studies on the stability of Pickering emulsions have primarily focused on macroscopic characterization, with limited investigation of the relationship between microscopic mechanical properties and macroscopic stability. This study aims to link macroscopic and microscopic mechanical properties and investigates the effects of different protein–chitosan composite systems on Pickering emulsion stability. By preparing Pickering emulsions with different protein bases and combining macroscopic rheology and microscopic particle size analysis with optical tweezer measurements of droplet–droplet interactions, we systematically elucidated the mechanical stability of the emulsions. The results show that different protein-based emulsions exhibit significant differences in rheological properties, particle size distribution, and microscopic mechanical stability. Among these emulsions, soy and pea protein-based emulsions and their mayonnaise formulations demonstrate superior mechanical stability. This study provides experimental evidence and new insights for improving the stability of protein-based Pickering emulsions in food applications.