The Impact of Perilla Oil Content on the Characteristics of Whey Protein/ Sanshoamides Emulsion

To enhance the stability of sanshoamides and expand the application of sanshoamides, this study utilized whey protein (WP) as an emulsifier to prepare perilla oil emulsions. This approach aimed to improve both the stability of sanshoamides. This study investigated the effects of 40%~80% oil phase volume fractions (v/v) on the formation and structure of the emulsions. And the analysis focused on the microstructure, particle size, rheological properties and stability of the emulsions loaded with sanshoamides. Microscopic results demonstrated that the emulsions had good emulsion droplet characteristics, which provided a physical basis for their stability. The emulsion containing 70% perilla oil exhibited uniform droplet distribution, smaller particle size, higher absolute zeta potential, and stronger emulsification ability, along with high centrifugal and thermal stability. Rheological analysis revealed that it was found that the emulsion exhibited elastic-like behavior and shear-thinning phenomenon. After 21 d of storage, when the perilla oil content was 70%, the emulsions still did not delaminate, indicating high storage stability and oxidative stability. Compared to free sanshoamides, the emulsion significantly slowed lipid oxidation and enhanced the retention of sanshoamides. The degradation rate of the emulsion containing 70% perilla oil decreased over time during storage. In summary, increasing the oil content in the emulsion loaded with sanshoamides can enhance the stability of both the sanshoamides and the emulsion, while also slowing the rate of lipid oxidation. This study aims to provide a theoretical basis for the loading and delivery of sanshoamides, as well as a technical reference for the construction of highly stable emulsion systems.