Wheeler T L, Shackelford S D, Koohmaraie M
Roman L. Hruska U.S. Meat Animal Research Center, ARS, USDA, Clay Center, NE 68933-0166, USA.
J Anim Sci. 1999 Apr;77(4):882-8. doi: 10.2527/1999.774882x.
The objective of this experiment was to determine the impact of USDA quality grade on the palatability of "tender" longissimus when cooked well done. Warner-Bratzler shear force was determined on longissimus thoracis steaks aged 3 or 14 d postmortem (cooked to 70 degrees C) from carcasses of 692 steers and heifers. Steaks from 31 carcasses with Modest or Moderate marbling scores (Top Choice) and steaks from 31 carcasses with Slight00 to Slight40 marbling scores (Low Select) were selected for this experiment from carcasses identified as "tender" (shear force < 5.0 kg at 3 d postmortem). Longissimus thoracis steaks with 3 or 14 d of postmortem aging were cooked to 80 degrees C and evaluated by a trained sensory descriptive attribute panel. Top Choice steaks had higher (P < .05) juiciness (5.8 vs 5.3) and beef flavor intensity ratings (4.9 vs 4.6) than Low Select steaks. Aging of steaks for 14, rather than 3, d postmortem improved (P < .05) beef flavor intensity rating (4.8 vs 4.7) but not (P > .05) juiciness rating (5.6 vs 5.5). The interaction (P < .05) of quality grade and aging time for tenderness rating indicated that Top Choice steaks were more tender (P < .05) with 3 d of aging than steaks from Low Select carcasses (6.3 vs 5.8), but steaks from Top Choice and Low Select carcasses had similar (P > .05) tenderness ratings after 14 d of aging (7.0 and 6.8). Compared to palatability of steaks from Low Select carcasses, the palatability of steaks from Top Choice carcasses was less affected by elevated degree of doneness in "tender" longissimus thoracis, especially when steaks were aged for only 3 d. Although differences in sensory traits between Top Choice and Low Select steaks were small, the consumers who cook beef well done may benefit from implementation of tenderness classification in conjunction with USDA quality grade.
本实验的目的是确定美国农业部质量等级对“嫩”背最长肌在全熟烹饪时适口性的影响。对692头公牛和母牛胴体的胸段背最长肌牛排进行了沃纳-布拉茨勒剪切力测定，这些牛排宰后成熟3天或14天（烹饪至70摄氏度）。从被鉴定为“嫩”（宰后3天剪切力<5.0千克）的胴体中，挑选出31头大理石花纹评分中等或适中（特选级）的胴体上的牛排，以及31头大理石花纹评分轻微00至轻微40（低选级）的胴体上的牛排用于本实验。将宰后成熟3天或14天的胸段背最长肌牛排烹饪至80摄氏度，并由经过训练的感官描述属性评定小组进行评估。特选级牛排的多汁性评分（5.8对5.3）和牛肉风味强度评分（4.9对4.6）高于低选级牛排（P<.05）。牛排宰后成熟14天而非3天，牛肉风味强度评分有所提高（P<.05）（4.8对4.7），但多汁性评分没有提高（P>.05）（5.6对5.5）。嫩度评分的质量等级和成熟时间的交互作用（P<.05）表明，特选级牛排成熟3天时比低选级胴体上的牛排更嫩（P<.05）（6.3对5.8），但特选级和低选级胴体上的牛排成熟14天后嫩度评分相似（P>.05）（7.0和6.8）。与低选级胴体上的牛排适口性相比，特选级胴体上的牛排适口性受“嫩”胸段背最长肌熟度升高的影响较小，尤其是牛排仅成熟3天时。尽管特选级和低选级牛排的感官特性差异较小，但将嫩度分级与美国农业部质量等级结合实施，可能会使喜欢将牛肉全熟烹饪的消费者受益。
