Effects of L-Lys on the Quality Characteristics and Oxidation Degree of Yak Meat under MDA Induced Oxidation

Abstract

In order to study the effects of L-Lys on the quality characteristics and protein oxidation of yak meat induced by MDA. In this study, MDA was used as the simulated oxidation system, and yak meat were used as the research objects. The changes of edible quality, lipid oxidation, protein oxidation and muscle histological characteristics during storage were measured after yak meat treated with different concentrations of L-Lys and MDA. The results showed that 10 mmol/L L-Lys could reduce the increase of pH caused by MDA, alleviate the excessive increase of hardness and chewiness, and significantly inhibit the conversion of oxygenated myoglobin into high iron myoglobin, thereby increasing the L* value and a* value (P<0.05), so as to maintain good color. In addition, L-Lys had a significant inhibitory effect on MDA by inducing lipid and protein oxidation, which was manifested by the decrease of POV and TBARS (P<0.05), and the significant increase of sulfhydryl and active sulfhydryl (P<0.05). L-Lys of 10 mmol/L could also significantly inhibit protein carbonylation (P<0.05) in the early stage of storage. Meanwhile, L-Lys could maintain the integrity of muscle fiber structure and reduce MFI to a certain extent. The above results indicated that L-Lys could delay MDA induced lipid and protein oxidation in meat to a certain extent through concentration dependence, thereby improving the oxidative stability of meat and reducing the deterioration of meat quality. In general, L-Lys at 10 mmol/L had a better effect. Therefore, L-Lys was proved to have a potential application value in inhibiting the oxidation of yak meat products and improving their edible quality.

Keywords

• l-lysine
• mda
• yak meat
• quality characteristics
• protein oxidation