Effects of high hydrostatic pressure treatment on the structural properties of interfacial protein of rabbit myosin emulsion

Abstract

High hydrostatic pressure (HHP) treatment (< 200 MPa) has been known to increase the emulsification properties of myosin. However, the relationship between interfacial elasticity and emulsion stability is complicated. Therefore, this study was focused on exploring the effects of high hydrostatic pressure on the physiochemical and structural properties of interfacial proteins within a stabilized oil-in-water (O/W) rabbit myosin emulsion. We analyzed the adsorption rate and structure of interfacial proteins pressurized under 0.1 [control], 100, 150, and 200 MPa prior to emulsion preparation. As the pressure was increased from 0.1 to 150 MPa, the adsorption rate of interfacial protein increased. HHP treatment caused myosin to unfold, which enhanced the exposure of reactive sulfhydryl and hydrophobic groups. Furthermore, the frequency of hydrogen bonding and hydrophobic interactions increased. As hydrogen bonding increased, the secondary structure of myosin became more stable. As the pressure increased to 200 MPa, the interfacial myosin aggregated, displaying a decreased surface hydrophobicity and reactive sulfhydryl groups (P < 0.05) and thus the emulsion stability decreased. In conclusion, HHP treatment of myosin at 150 MPa significantly improved the stability of the myosin emulsion. Industrial relevanceMyosin is an important protein in meat and its emulsion stability can be enhanced by HHP. This study reveals the conformational mechanism by which HHP improves the stability of myosin emulsions, providing potential theoretical basis for the application of HHP treatment to improve the quality of emulsified meat products as a non-thermal processing technology in the practical production.