The Effect of Three Temperature Conditioning Treatments and Subcutaneous Fat Removal on Lamb Quality

Abstract

Thirty Suffolk and Suffolk crossbred ewe lambs w e r e blocked on live weight and randomly assigned to carcass conditioning treatments of 0, 16 and 23C for 8 h. Subcutaneous fat over the longissimus muscle and kidney fat were removed from the left side of each carcass during slaughter. The 23C conditioning treatment had significantly higher temperatures from 2 through 12 h compared with 0C and 16C treatments, and the 16C treatment had higher (P < .05) temperatures from 2 through 12 h compared with the 0~ treatment. There was an interaction between conditioning treatments and fat removal for postmortem temperature. The intact sides had significantly higher temperatures at 2 and 4 h for the 0C treatment, whereas trimmed sides had higher (P < .05) longissimus muscle temperatures than the intact sides at 6 h postmortem for both the 16 and 23C treatments. The conditioning treatments increased the pH decline; the 23C treatment had lower pH values at almost all time periods compared with the 0C treatment. The 16~ treatment had lower (P < .05) pH values at 6, 8 and 12 h postmortem than the 0~ treatment. The 16C treatment improved tenderness of the longissimus muscle, as indicated by lower shear force (3.45 kg) and higher sensory panel tenderness ratings (4.80) compared with the 0~ (4.74 kg and 3.82) and 23C (4.63 kg and 3.61) treatments. Fat removal had no significant effect on pH, sarcomere length, shear force or sensory panel ratings. The 16~ conditioning treatment improved lamb tenderness compared with 0 and 23C, whereas fat removal at slaughter had no significant effect on lamb quality. (