Department of Animal and Food Sciences, Texas Tech University, Lubbock 79409, USA.
J Anim Sci. 2012 Oct;90(10):3584-95. doi: 10.2527/jas.2012-5159. Epub 2012 Jul 31.
An experiment was conducted to determine the effects of zilpaterol hydrochloride mM supplementation (ZH; 8.3 mg/kg on a DM basis for 20 d) and calcium chloride injection [CaCl(2), 200 at 5% (wt/wt) at 72 h postmortem] on palatability traits of beef (Bos taurus) strip loin steaks. Select (USDA) strip loins were obtained from control (no ZH = 19) and ZH-supplemented carcasses (n = 20). Right and left sides were selected alternatively to serve as a control (no INJ) or CaCl(2)-injected (INJ) and stored at 4°C. Before injecting the subprimals (72 h postmortem), 2 steaks were cut for proximate, sarcomere length, and myofibrillar fragmentation index (MFI) analyses. At 7 d postmortem each strip loin was portioned into steaks, vacuum packaged, and aged for the appropriate period for Warner-Bratzler shear force (WBSF; 7, 14, 21, and 28 d postmortem), trained sensory analysis (14 and 21 d postmortem), purge loss (7 d), and MFI (3, 7, 14, 21, and 28 d postmortem). Results indicated steaks from both ZH supplementation and INJ had reduced WBSF values as days of postmortem aging increased. The WBSF values of ZH steaks were greater (P < 0.05) than no ZH steaks at each postmortem aging period. The INJ steaks had lower WBSF values (P < 0.05) than non-injected steaks. A greater percentage (91 vs. 71%) of steaks had WBSF values < 4.6 kg from steers with no ZH supplementation at 7 d postmortem, but the percentage did not differ (P > 0.05) due to ZH at 14, 21, or 28 d or due to INJ at any aging period. Trained panelists rated tenderness less in ZH steaks than steaks with no ZH at 14 d and 21 d. However, INJ improved (P < 0.05) the tenderness ratings and flavor intensity of the trained panelists, compared with their non-injected cohorts at 21 d. Zilpaterol hydrochloride supplementation reduced (P < 0.05) MFI values, but INJ resulted in greater (P < 0.05) MFI values compared with no INJ. Subprimals from ZH and INJ showed greater purge loss (P < 0.05). Although no interactions were found with ZH and CaCl(2), injecting USDA Select strip loins from ZH-fed cattle can help reduce the normal WBSF variation as it does in steaks from non-ZH-fed cattle.
进行了一项实验，以确定盐酸齐帕特罗（zilpaterol hydrochloride）mM 补充剂（ZH；基于 DM 的 8.3mg/kg，持续 20 天）和氯化钙注射液[CaCl(2)，在死后 72 小时以 5%（wt/wt）注射]对牛肉（Bos taurus）里脊牛排的适口性特性的影响。从对照（无 ZH=19）和 ZH 补充剂处理的胴体（n=20）中选择（USDA）里脊。右侧和左侧交替选择作为对照（无 INJ）或氯化钙（INJ）注射，并在 4°C 下储存。在注射半胴体（死后 72 小时）之前，切取 2 块牛排进行近侧分析、肌节长度和肌原纤维断裂指数（MFI）分析。在死后 7 天，每个里脊牛排被分成牛排，真空包装，并在适当的时间进行老化，以进行 Warner-Bratzler 剪切力（WBSF；死后 7、14、21 和 28 天）、训练有素的感官分析（死后 14 和 21 天）、渗出损失（7 天）和 MFI（死后 3、7、14、21 和 28 天）分析。结果表明，随着死后老化天数的增加，来自 ZH 补充剂和 INJ 的牛排的 WBSF 值降低。与无 ZH 处理的牛排相比，ZH 处理的牛排的 WBSF 值更高（P<0.05）。INJ 处理的牛排的 WBSF 值较低（P<0.05）。在死后 7 天，无 ZH 补充的牛的牛排中有更高比例（91%比 71%）的 WBSF 值<4.6kg，但由于 ZH 在 14、21 或 28 天或由于 INJ 在任何老化期都没有差异（P>0.05）。训练有素的品尝小组在 14 天和 21 天时，对无 ZH 处理的牛排的嫩度评分低于有 ZH 处理的牛排。然而，与未经注射的对照组相比，INJ 在 21 天时提高了（P<0.05）训练有素的品尝小组的嫩度和风味强度评分。盐酸齐帕特罗的补充降低了（P<0.05）MFI 值，但与未经注射的对照组相比，INJ 导致了更高（P<0.05）的 MFI 值。来自 ZH 和 INJ 的半胴体的渗出损失更高（P<0.05）。尽管没有发现 ZH 和 CaCl(2)之间的相互作用，但给 ZH 喂养的牛注射 USDA 选择的里脊可以帮助减少正常的 WBSF 变化，就像非 ZH 喂养的牛的牛排一样。
