Shackelford S D, Wheeler T L, Koohmaraie M
Roman L. Hruska U.S. Meat Animal Research Center, USDA, ARS, Clay Center, NE 68933-0166, USA.
J Anim Sci. 2004 Mar;82(3):802-7. doi: 10.2527/2004.823802x.
Experiments were conducted to compare the effects of two cookery methods, two shear force procedures, and sampling location within non-callipyge and callipyge lamb LM on the magnitude, variance, and repeatability of LM shear force data. In Exp. 1, 15 non-callipyge and 15 callipyge carcasses were sampled, and Warner-Bratzler shear force (WBSF) was determined for both sides of each carcass at three locations along the length (anterior to posterior) of the LM, whereas slice shear force (SSF) was determined for both sides of each carcass at only one location. For approximately half the carcasses within each genotype, LM chops were cooked for a constant amount of time using a belt grill, and chops of the remaining carcasses were cooked to a constant endpoint temperature using open-hearth electric broilers. Regardless of cooking method and sampling location, repeatability estimates were at least 0.8 for LM WBSF and SSF. For WBSF, repeatability estimates were slightly higher at the anterior location (0.93 to 0.98) than the posterior location (0.88 to 0.90). The difference in repeatability between locations was probably a function of a greater level of variation in shear force at the anterior location. For callipyge LM, WBSF was higher (P < 0.001) at the anterior location than at the middle or posterior locations. For non-callipyge LM, WBSF was lower (P < 0.001) at the anterior location than at the middle or posterior locations. Consequently, the difference in WBSF between callipyge and non-callipyge LM was largest at the anterior location. Experiment 2 was conducted to obtain an estimate of the repeatability of SSF for lamb LM chops cooked with the belt grill using a larger number of animals (n = 87). In Exp. 2, LM chops were obtained from matching locations of both sides of 44 non-callipyge and 43 callipyge carcasses. Chops were cooked with a belt grill and SSF was measured, and repeatability was estimated to be 0.95. Repeatable estimates of lamb LM tenderness can be achieved either by cooking to a constant endpoint temperature with electric broilers or cooking for a constant amount of time with a belt grill. Likewise, repeatable estimates of lamb LM tenderness can be achieved with WBSF or SSF. However, use of belt grill cookery and the SSF technique could decrease time requirements which would decrease research costs.
进行了实验，以比较两种烹饪方法、两种剪切力测定程序以及非臀肌肥大和臀肌肥大羔羊腰大肌内不同采样位置对腰大肌剪切力数据的大小、方差和重复性的影响。在实验1中，采集了15只非臀肌肥大和15只臀肌肥大的胴体，沿着腰大肌长度（从前到后）的三个位置测定了每只胴体两侧的沃纳-布拉茨勒剪切力（WBSF），而仅在一个位置测定了每只胴体两侧的切片剪切力（SSF）。对于每种基因型的大约一半胴体，使用带式烤架将腰大肌排骨烹饪固定时间，其余胴体的排骨使用平炉电烤炉烹饪至固定的终点温度。无论烹饪方法和采样位置如何，腰大肌WBSF和SSF的重复性估计值至少为0.8。对于WBSF，前部位置的重复性估计值（0.93至0.98）略高于后部位置（0.88至0.90）。位置之间重复性的差异可能是由于前部位置剪切力变化水平较高所致。对于臀肌肥大的腰大肌，前部位置的WBSF高于中部或后部位置（P<0.001）。对于非臀肌肥大的腰大肌，前部位置的WBSF低于中部或后部位置（P<0.）。因此，臀肌肥大和非臀肌肥大腰大肌之间的WBSF差异在前部位置最大。进行实验2是为了使用更多动物（n = 87）来估计用带式烤架烹饪的羔羊腰大肌排骨的SSF重复性。在实验2中，从44只非臀肌肥大和43只臀肌肥大胴体两侧的匹配位置获取腰大肌排骨。用带式烤架烹饪排骨并测量SSF，重复性估计为0.95。通过用电烤炉烹饪至固定的终点温度或用带式烤架烹饪固定时间，都可以实现羔羊腰大肌嫩度的可重复估计。同样，使用WBSF或SSF也可以实现羔羊腰大肌嫩度的可重复估计。然而，使用带式烤架烹饪和SSF技术可以减少时间需求，从而降低研究成本。
