the problem of meat tenderness is of great concern among

producers because this parameter has become the most

important criteria upon which consumers judge meat quality.

This problem is especially critical when it is also a proven

fact that one of every four sensorial experiences of the

consumer is unsatisfactory when eating meat. This paper

overviews the main aspects determining meat tenderness

such has structural and chemical composition of meat,

muscular contraction, biochemical postmortem changes

(rigor mortis and meant aging) and the general effects caused

by industrial processing when cooking and freezing. General

methods for improving meat tenderness and the biochemical

activity of the calcium ion dependent papain like cisteine

proteases (CALPAIN) are also reviewed.

Keywords: meat, biochemistry, tenderness, calpain, enzymes.