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


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Published in Beef Research Program Progress Report (1993) No. 4 (Part 1): 141-142


The recently completed National Beef Tenderness Survey revealed that current beef production practices result in considerable variation in meat tenderness and an unacceptable percentage of tough meat, particularly round and chuck cuts. It has been known for several years that meat from Bos indicus cattle was tougher than meat from Bos taurus cattle and that Bos indicus-influenced cattle make up approximately 25% of the beef cattle in the U.S. In addition, as the beef industry moves towards leaner beef, many production systems that decrease fatness also result in decreased tenderness (i.e., bulls vs steers, forage feeding, growth promotants). Furthermore, the 1992 Beef Quality Audit reported that retailers, restaurateurs and meat purveyors all listed tenderness as one of their top ten problems. Clearly, some means of improving and ensuring meat tenderness is needed.

A potential solution to this problem already exists. It has been demonstrated by U.S. Meat Animal Research Center scientists that meat tenderness can be improved dramatically at 1 day postmortem by infusing whole carcasses or injecting specific cuts with a calcium chloride solution within 1 hr postmortem. The addition of calcium activates a naturally occurring enzyme (calpain) in the muscle which accelerates postmortem tenderization so that uniformly tender meat is consistently obtained at 1 day postmortem. This process has been used successfully in normal lambs, lambs fed a β-agonist, Bos indicus cattle and 12-yr old cows.

However, industry adoption of this technology will probably require hot-boning for prerigor injection or may be more likely if it could be applied after 24 hr chilling, rather than immediately postmortem, in order to avoid conflict with inspection and grading procedures. Thus, several experiments were conducted to evaluate the use of calcium chloride injection in hot-boned prerigor muscles (at 30 min postmortem) and to evaluate the application of the injection process in postrigor meat (at 24 hr postmortem).