U.S. Department of Agriculture: Agricultural Research Service, Lincoln, Nebraska


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Published in Beef Research Program Progress Report (1988) No. 3: 47-48


Tenderness is the prominent quality determinant and probably the most important sensory characteristic of beef steak and roast meat. Currently postmortem aging (storage of carcass at refrigerated temperatures for 8 to 14 days) appears to be the best method for producing tender meat. Although the improvement in meat tenderness as a result of postmortem aging is measurable both subjectively and objectively, the exact mechanism responsible for this improvement in tenderness is unknown.

It is well known that different muscles within the same carcass react differently to postmortem storage; for example, tenderloin is tender to begin with and does not improve significantly with postmortem storage, while ribeye is the toughest muscle initially and improves greatly with postmortem storage. The purpose of these experiments was to attempt to answer the following questions: 1)Why are some muscles (e.g., tenderloin) tender at 24 hr postmortem and nonresponsive to postmortem aging? and 2) Why do some muscles (e.g., ribeye and tenderloin) respond differently to postmortem aging?