Bass P D, Scanga J A, Chapman P L, Smith G C, Tatum J D, Belk K E
Department of Animal Sciences, Colorado State University, Fort Collins 80523, USA.
J Anim Sci. 2008 Jul;86(7):1658-68. doi: 10.2527/jas.2007-0688. Epub 2008 Mar 14.
Effects of the dark-cutting condition were examined on commercially slaughtered beef carcass sides that were classified into groups exhibiting 1/3, 1/2, and full degrees of the dark-cutting (DEGDC) condition, as evaluated by a USDA-Agricultural Marketing Service grader (n = 20 per group). Twenty-nine muscles of each carcass side were evaluated to determine the ultimate pH and color (L*, a*, and b*). Fourteen beef muscles (biceps femoris, deep pectoral, chuck complexus, gluteus medius, infraspinatus, latissimus dorsi, psoas major, longissimus thoracis, longissimus lumborum, semimembranosus, semitendinosus, triceps brachii long head, tensor fasciae latae, and vastus lateralis) were evaluated using Warner-Bratzler Shear force (WBSF) and a trained sensory panel. The muscle x DEGDC interaction was significant for ultimate pH, L*, a*, and b* values (P < 0.05). When ultimate pH values of individual muscles were compared with the same muscles evaluated in a previous study, the 1/3, 1/2, and full DEGDC had 7, 9, and 5 muscles, respectively, that fell within a computed 95% prediction limit of what would be considered as a normal pH but were more variable as measured by within-class CV. Color values (L*, a*, and b*) of the muscles from dark-cutting carcasses were numerically lower than those from the normal carcasses. A survey designed to determine the ideal color range of beef lean for retail meat merchandisers (n = 34) and food service chefs (n = 33) across the United States resulted in data analyzed using principal components analysis of L*, a*, and b* values for muscles dissected in the study to estimate the true values for dark-cutting carcasses. Muscles that were within an acceptable color value range for food service chefs had the potential to add between $42.29 to $26.44 and $14.71 to $8.11 per side when valued at Choice and Select prices, respectively. Muscles that were within an acceptable color value range had the potential to add between $30.39 to $16.74 and $10.37 to $5.03 per side for retail meat merchandisers when acceptable muscles were valued at Choice and Select prices, respectively. No muscle x DEGDC interactions were detected for WBSF and sensory panel scores (P > 0.05), but differences were detected among muscles (P < 0.05). Several muscles were considered salvageable from the dark-cutting carcasses that were evaluated, and no significant differences in sensory scores or WBSF between DEGDC classes suggested equal sensory expectations for muscles from dark-cutting carcasses.
研究了暗切条件对商业屠宰牛肉胴体半边的影响，这些胴体半边被美国农业部农产品销售服务局分级员分为呈现1/3、1/2和完全暗切程度（DEGDC）的组（每组n = 20）。对每个胴体半边的29块肌肉进行评估，以确定最终pH值和颜色（L*、a和b）。使用沃纳-布拉茨勒剪切力（WBSF）和一个经过训练的感官评定小组对14块牛肉肌肉（股二头肌、胸深肌、颈夹肌、臀中肌、冈下肌、背阔肌、腰大肌、胸最长肌、腰最长肌、半膜肌、半腱肌、肱三头肌长头、阔筋膜张肌和股外侧肌）进行评估。肌肉×DEGDC交互作用对最终pH值、L*、a和b值具有显著影响（P < 0.05）。当将个体肌肉的最终pH值与先前研究中评估的相同肌肉进行比较时，1/3、1/2和完全DEGDC分别有7块、9块和5块肌肉落在计算出的正常pH值的95%预测范围内，但以组内变异系数衡量时更具变异性。暗切胴体肌肉的颜色值（L*、a*和b*）在数值上低于正常胴体肌肉的颜色值。一项旨在确定美国各地零售肉类商（n = 34）和食品服务厨师（n = 33）理想牛肉瘦肉颜色范围的调查，其结果数据通过对研究中解剖的肌肉的L*、a*和b*值进行主成分分析来分析，以估计暗切胴体的真实值。对于食品服务厨师来说，颜色值在可接受范围内的肌肉，按精选级和特选级价格估值时，每半边分别有可能增加42.29美元至26.44美元以及14.71美元至8.11美元。对于零售肉类商来说，颜色值在可接受范围内的肌肉，按精选级和特选级价格估值时，每半边分别有可能增加30.39美元至16.74美元以及10.37美元至5.03美元。对于WBSF和感官评定小组评分，未检测到肌肉×DEGDC交互作用（P > 0.05），但在肌肉之间检测到差异（P < 0.05）。在评估的暗切胴体中，有几块肌肉被认为是可挽救的，并且在DEGDC等级之间，感官评分或WBSF没有显著差异，这表明对暗切胴体肌肉的感官期望相同。
