No abstract

Juárez, M., Larsen, I. L., Klassen, M. and Aalhus, J. L. 2013. Canadian beef tenderness survey: 2001–2011. Can. J. Anim. Sci. 93: 89–97. A large survey across Canada was developed collecting retail beef samples in 2001 (702 steaks) and 2011 (602 steaks). The samples (strip loin, top sirloin, inside round and cross-rib steaks) were evaluated for instrumental tenderness using standard procedures for sampling, storage, cooking and texture evaluation. New equations were also developed in order to compare the results obtained in these studies with consumer thresholds developed in Canada and the United States of America. In general, retail steaks collected in 2011 weighed less and showed higher fat thickness than those from 2001. Regarding tenderness, a significant improvement was observed, especially for strip loin and top sirloin steaks between 2001 and 2011. Using US threshold categories, the percentage of “tender” samples improved for the strip loin (2001=89%; 2011=99%), top sirloin (2001=70%; 2011=87%), inside round (2001=52%; 2011=61%) and cross-rib (2001=65%; 2011=76%) steaks. Similarly, the percentage of “tough” samples shifted from 5, 8 27 and 13% for the strip loin, top sirloin, inside round and cross-rib steaks in 2001 to 1, 5, 13, and 8%, respectively, in 2011. Similar improvements were observed when using the more descriptive four-category Canadian threshold system. These improvements may be due to changes in the animal population, production systems, carcass processing and distribution/handling prior to display in Canada.

J. L. 2014. SHORT COMMUNICATION: Influence of some meat quality parameters on beef tenderness. Can. J. Anim. Sci. 94: 455Á458. Steaks from longissimus lumborum and semimembranosus muscles, aged 2 or 27 d, were obtained from a population of steers (n 0112) managed to produce a range in tenderness (shear force range from 2.57 to 17.2 kg). All available carcass (live weight, hot commercial weight, pH, temperature, marbling, rib-eye area) and meat (objective colour, cook loss, cook time, WarnerÁBratzler shear force, myoglobin content, proximate composition and collagen content) quality data were used for the analyses. Multivariate analyses determined which factors influenced tenderness between and within muscles, both before or after ageing. In unaged muscles, soluble collagen explained differences in tenderness among muscles, while factors related to the myofibrillar component explained differences within a muscle. In contrast, in aged muscles, total collagen content was related to tenderness among muscles and the percent soluble collagen content was related to tenderness differences within a muscle.