Abstract: Effects of hydrostatic high-pressure (HHP) treatment on sensory characteristic, microscopic structure of myofibrilsand shear force value of bovine and mutton skeletal muscle were studied. The function that HHP could promote meat tendernesswas also discussed. The sensory characteristics of bovine and mutton muscle varied a lot after HHP treatment: color faded,extension decreased and mortem flavor emerged. Under the condition of 700MPa pressure level, 25℃ and 20min of HHPtreatment,the remarkable variation could be seen in microscopic structure of myofibrils of bovine and mutton muscle. Sarcomereshrinkage occurred with obvious changes. The contraction rates of bovine and mutton sarcomere were 34.8% and 22.2%respectively. Meanwhile, Z-lines broke, M- lines degraded and I band became white. The shear force values of bovine(p<0.05)and mutton(p<0.01) skeletal muscle decreased remarkably. The research results indicated that HHP could improvethe tenderness of bovine and mutton skeletal muscle. The sensory characteristics of bovine and mutton muscle varied a lot afterHHP treatment: color faded, extensilility decreased and mortem flavor emerged. These changes were caused by too high treatmentof HHP. If the pressure, temperature and maintaining time were chosen properly, HHP could result in a goal of improvingtenderness, killing microorganisms and keeping the natural flavor of meat.

Key words: hydrostatic high-pressure, bovine and mutton skeletal muscle, tenderness