Effect of liveweight gain or loss on lamb meat quality

An experiment was undertaken to compare the palatability and muscle pH of meat from around 30 lambs per group that had over a 7-week period in early winter either gained 11 kg live weight, held weight, or lost 11 kg live weight. The cooked longissimus muscle from the gain and loss groups was tested for shear force value using 10 samples from each lamb in a MIRINZ tenderometer. Mean values of 15.5 and 14.2 force score units were recorded for the two groups respectively on a scale where a value of 40 is bordering on tough. A consumer panel rated roast leg meat for overall score, tenderness and flavour and the meat from all treatments was rated highly satisfactory. Mean ultimate pH values from the lambs on all treatments were low. The results indicate that lamb weight loss per se had no adverse effect on the quality of meat. Weight loss did not differentially remove carcass fat compared with other tissues but the tendency was in this direction.