Textural assessment of clenbuterol treatment in beef

Eight Charolais heifers (ca. 300 kg) were fed a diet containing either 0 (control) or 1 ppm clenbuterol during 5 weeks. Daily live weight gain was higher (p<0.01), by about 34%, in treated animals. They were slaughtered after a week of withdrawal. Activity of μ-calpain of meat from clenbuterol-fed heifers was lower (p<0.01) immediately post mortem, while activity of calpastatin was higher (p<0.05) than in meat from controls. According to sensory and instrumental data, meat from clenbuterol-fed heifers did not tenderise during aging, and was tougher (p<0.05) than control meat at 8th day post mortem. Both principal component analysis and multivariate discriminant analysis of a pool of data of the textural profile showed differences due to clenbuterol treatment at 24 h. The slope after yield (calculated from the Warner-Bratzler shearing force-deformation curve), was the only textural parameter affected (p<0.05) at 24 h by the treatment.