Prediction of beef carcass composition from organs and tissues of the non-carcass parts

Abstract

SummaryIndividual muscles, individual bones and fat depots from the non-carcass parts (head, foreshanks and tail) of 40 steers (chilled carcass weight 142–174 kg) were studied in an attempt to predict carcass composition more accurately than in an earlier study where the crude non-carcass parts, head, tongue, foreshanks and hindshanks were used.The technique did not improve the accuracy of prediction of muscle or bone. Carcass fat, which was calculated by difference in the earlier study, was predicted more accurately using intermandibular fat weight (requiring 3–4 min to obtain) plus fat thickness at the 12th rib. However, the accuracy of this prediction (carcass fatness range 14·0–33·6%, residual standard deviation 1·98%) was no greater than that using chilled side weight plus fat thickness at the 12th rib.Careful dissection and trimming of anatomical entities from the non-carcass parts therefore offered a slight advantage only in the prediction of carcass components over existing techniques.Substitution of hot side weight for chilled side weight, and sacral crest fat thickness for fat thickness at the 12th rib did not lead to a loss in the accuracy of prediction of muscle, bone or fat.