Effect of a low-voltage electrical stimulation on yak meat tenderness during postmortem aging.

This study evaluates the effect of a low-voltage electrical stimulation (ES) on the tenderness of yak longissimus muscle (LM). Samples from 16 yak bulls were divided into four treatment groups: normal chilling (NC), ES and chilling (ES & C) for 72 s (ES &C 72 s), ES & C for 90 s (ES & C 90 s), and ES & C for 108 s (ES & C 108 s). The temperature, the pH, the glycogen content, the Warner-Bratzler shear force (WBSF), the myofibril fragmentation index (MFI), and the muscle ultrastructure were determined during the course of postmortem aging.

Study on the effect of reactive oxygen species-mediated oxidative stress on the activation of mitochondrial apoptosis and the tenderness of yak meat.

This study investigated the effect of reactive oxygen species-mediated oxidative stress on activation of mitochondrial apoptosis and tenderness of yak meat during postmortem ageing. Oxidative stress degree, Ca levels, membrane permeability transition pore opening, mitochondrial membrane potential, apoptotic factors and the shear force were examined. Results showed that the ROS generated by HO significantly increased mitochondrial oxidative stress by decreasing the activities of superoxide dismutase, catalase and glutathione peroxidase, and increasing lipid peroxidation.

Effect of mitochondrial apoptotic activation through the mitochondrial membrane permeability transition pore on yak meat tenderness during postmortem aging.

The effect of membrane permeability transition pore dependent mitochondrial apoptotic activation on yak meat tenderness was investigated. Results indicate that MPTP opening increased significantly and the mitochondrial membrane potential decreased markedly in the early aging process (P<0.05).