CHARACTERISTICS OF LAMB CARCASSES OF CONTRASTING SUBJECTIVE MUSCULARITY

In order to compare characteristics of lamb carcasses with superior mu scularity (the European E class) with carcasses that did not fit the E specification, 114 E carcasses were individually matched for weight a nd fatness class with 114 Non-E carcasses. The carcasses (mean weight = 17 kg) were processed under commercial conditions into six trimmed, boneless cuts of the leg and saddle (inside, outside, knuckle, rump, s triploin and tenderloin) and two bone-in cuts (hind-shank and 7-rib ra ck). After adjustment for carcass weight, fatness (as assessed by fat depth C and tissue depth GR) and sex, the E-class group, relative to t he Non-E group, had a 4.3% higher yield of leg and saddle cuts, a 14.2 % higher leg muscularity index calculated from the weights of trimmed boneless cuts around the femur and femur length, a 13.6% higher muscle to bone ratio in the femur region, an 8.2% greater 'eye'-muscle depth (B), and a 3.7% greater 'eye'-muscle width (A) fall P < 0.001), All b oneless cuts except the knuckle were heavier for the E group. Carcasse s of female lambs had legs with higher muscle to bone ratios and a hig her yield from the leg plus saddle (both P < 0.01), but the mascularit y index was similar between sexes. It is concluded that although lamb carcasses subjectively selected as having higher muscularity will yiel d slightly move meat, this difference will be small compared with the gr eater muscle depth relative to bone length. The importance consumer s attach to carcass or cut shape over and above any association with m eat yield needs to be assessed.