Effects of High-pressure Processing on the Storage Properties of Yak Meat

To investigate the effect of high-pressure processing (HPP) on the quality of yak meat, yak meat was processed under pressure at 200, 400, and 600 MPa for 480 seconds, respectively, and the sensory, pH, microorganism, color, protein, and lipid oxidation of yak meat stored at 4 °C for 0, 4, 8, 12, and 16 days was determined. The results showed that HPP significantly lowered the total number of colonies and total volatile basic nitrogen (TVB-N) during storage (P<0.05), and extended the shelf life of yak meat. Yak meat was well preserved for 4~8 days from sensory perception. The L^* and b^* values of yak meat with HPP increased significantly (P<0.05). The a^* value increased significantly at 400 MPa (P<0.05) and remained at the highest level throughout storage, and the contents of various myoglobin (Mb) in the 400 MPa group also demonstrated excellent meat color stability. Whereas the a^* values decreased significantly under other pressure conditions (P<0.05). The carbonyl content and surface hydrophobicity of yak meat myofibrillar protein (MP) were increased, while sulfhydryl content were decreased, and TBARS of yak meat were elevated. According to Pearson correlation analysis, pressure, protein oxidation, lipid oxidation, and microbes were all associated with changes in yak meat quality under HHP (P<0.05). In conclusion, although HPP accelerated the oxidation of protein and lipids, the use of appropriate pressure was conducive to maintaining the meat color stability and sensory quality of yak meat, providing a reference for the application of yak meat with HPP.