Study on the Promotion of Mitochondrial Pathway Apoptosis and Muscle Tenderization in Postmortem Tibetan Sheep Meat by Cold Atmospheric Plasma Treatment.

Oula Tibetan sheep meat is rich in nutrients, but its tenderness is relatively poor. Therefore, exploring meat tenderization methods is crucial. Previous studies have indicated that reactive species generated by plasma promote mitochondrial dysfunction and induce apoptosis in tumor cells. However, the impacts of plasma treatment on mitochondrial pathway apoptosis and the tenderization of Oula Tibetan sheep meat have not been reported. This study aimed to explore the effects of cold atmospheric plasma (CAP) treatment on mitochondrial pathway apoptosis and meat tenderness of Tibetan sheep meat during postmortem aging. The results showed that after CAP treatment, reactive oxygen species (ROS) and nitric oxide (NO) content increased, pH value and ATP content decreased, resulting in an increase in mitochondrial permeability transition pore (MPTP) opening, a decrease in succinate dehydrogenase (SDH) activity, Cytochrome c (Cyt-c) reduction level and mitochondrial membrane potential (MMP), and an increase in Caspase-3/9 activity, promoting the occurrence of mitochondrial pathway apoptosis. Meanwhile, myofibril fragmentation index(MFI) increased, shear force value decreased and the mitochondrial structure was obviously damaged. The results of the correlation analysis showed that the degree of mitochondrial damage was significantly positively correlated with the tenderization of the meat during postmortem aging. Therefore, CAP treatment promoted mitochondrial pathway apoptosis and muscle tenderization during postmortem aging of Tibetan sheep meat by increasing the content of ROS and NO and altering the intracellular environment of muscle cells, thereby intensifying mitochondrial damage. The study can provide a theoretical basis for CAP treatment to improve the tenderness of Tibetan sheep meat. PRACTICAL APPLICATIONS: The results of this study indicate that CAP treatment can improve the tenderness of Tibetan sheep meat by promoting apoptosis in the mitochondrial pathway. Therefore, CAP treatment may be used as a nonthermal processing technology to effectively improve the tenderness of Tibetan sheep meat.