Evolution of the structure of meat protein particles at the oil–water interface facilitates the ultra-long storage stability of high internal pickering emulsion

Abstract

Myosin, a myofibrillar protein, acts as a key meat emulsifying agent. Actin, tropomyosin, and troponin are also myofibrillar proteins, however, the role of these proteins in the emulsification process remains unclear. In this study, we aimed to determine the meat emulsifying capacities of actin, tropomyosin, and troponin. We fabricated meat protein particles (MPs) with actin, tropomyosin and troponin, under different pH conditions. Under acidic conditions, in the bulk phase solution, protein aggregates with block-like characteristics were formed by the hydrophobic interaction, which disassembled and adsorbed on the surface of the oil droplets during the emulsification process. During the emulsion storage process, the meat particle stabilizer was transformed into a structural agent with polygonal network characteristics, which elicited changes in emulsion droplet morphology (to loose, close, and ultra-close packing). This resulted in the following emulsion properties: ultra-long stability and good rheological properties. However, this phenomenon was not observed under neutral and alkaline conditions, in high internal Pickering emulsion (HIPPEs) constructed of aggregates dominated by coarse beaded characteristics. Overall, protein particles with different structural characteristics, in bulk phase solution, influence the structural evolution and properties of HIPPEs. The study findings provide scientific guidance for meat protein hierarchical utilization in the production of emulsion-based food products, under high efficiency and low-cost conditions.