Kuber P S, Duckett S K, Busboom J R, Snowder G D, Dodson M V, Vierck J L, Bailey J F
Department of Animal Sciences, Washington State University, Pullman, WA 99164-6310, USA.
Meat Sci. 2003 Mar;63(3):325-31. doi: 10.1016/s0309-1740(02)00089-x.
The purpose of this study was to determine if tenderness of callipyge (CLPG) longissimus dorsi muscle (LM) could be improved by: (1) extending the aging period to 48 days postmortem or (2) preventing rigor shortening by clamping. In CLPG and normal (NML) chops respectively, initial Warner-Bratzler shear values (WBS) were lower (P<0.05) in clamped (CL) (5.5 and 3.6 kg) compared to unclamped (UCL) (7.4 and 4.9 kg) LM. In CLPG, an acceptable WBS (3.6 kg) was reached at 48 days PM, whereas, NML lambs reached an acceptable level (3.8 kg) by 3 days PM. Sarcomere lengths (SL) of CL (1.68 μm) were longer (P <0.05) than for UCL (1.44 μm) and were negatively correlated with WBS (r=-0.55; P<0.1). The appearance of Troponin-T (TNT) degradation product coincided with tender WBS values; 3 days postmortem in NML UCL and 48 days postmortem in CLPG. In conclusion, clamping reduced WBS possibly by reducing rigor shortening. Extended aging resulted in CLPG LM with acceptable WBS values, concurrent with the appearance of TNT degradation products.
本研究的目的是确定是否可以通过以下方式改善臀肌肥大（CLPG）背最长肌（LM）的嫩度：（1）将成熟时间延长至宰后48天，或（2）通过夹紧防止僵直缩短。在CLPG和正常（NML）排骨中，与未夹紧（UCL）（7.4和4.9千克）的LM相比，夹紧（CL）（5.5和3.6千克）的初始Warner-Bratzler剪切值（WBS）较低（P<0.05）。在CLPG中，宰后48天达到了可接受的WBS（3.6千克），而NML羔羊在宰后3天达到了可接受水平（3.8千克）。CL的肌节长度（SL）（1.68μm）比UCL（1.44μm）长（P<0.05），并且与WBS呈负相关（r=-0.55；P<0.1）。肌钙蛋白-T（TNT）降解产物的出现与嫩的WBS值一致；NML UCL宰后3天和CLPG宰后48天。总之，夹紧可能通过减少僵直缩短来降低WBS。延长成熟时间导致CLPG的LM具有可接受的WBS值，同时出现TNT降解产物。
