Abstract: μ-calpain is a component of calpain system. It exists in almost all of the animal cells. As a calcium activated neutral protease, it has important role in the proteolytic degradation of myofibrilla that results in postmortem tenderization. In this article we reviewed the structure of μ-calpain, characteristics of its function, detection of its activity, and the relationship between genetic variation in the gene and tenderness of meat. 

Key words: μ-calpain; structure; function; activity; tenderness; molecular marker