Kerth C R, Cain T L, Jackson S P, Ramsey C B, Miller M F
Department of Animal Science and Food Technology, Texas Tech University, Lubbock 79409-2162, USA.
J Anim Sci. 1999 Nov;77(11):2951-5. doi: 10.2527/1999.77112951x.
The objective of this study was to determine effects of electrical stimulation (ES) on muscle quality and sensory traits of 12 Hampshire x Rambouillet callipyge lambs. One side of each carcass was randomly assigned to an ES treatment of 550 V and 60 Hz of electricity for 2 s on and 2 s off 15 times. The other side was a nonstimulated control (NES). Heated calpastatin, sarcomere length, myofibrillar fragmentation index (MFI), Warner-Bratzler shear (WBS), and trained sensory panel values were measured on the semitendinosus (ST), semimembranosus (SM), longissimus (ML), supraspinatus (SP), and triceps brachii (TB) muscles. Electrically stimulating the carcass sides induced a more rapid (P = .001) pH decline in the longissimus muscle, and ES sides had a brighter (P = .001) red color of loineye than nonstimulated sides. At d 14 of storage (2 degrees C), the TB had the highest (P < .05) MFI value, indicating more protein degradation, and the ST and ML muscles had the lowest MFI (P = .008). Regardless of ES treatment, SM and ML had the highest (P < .05) WBS values. The ST muscle had higher (P < .05) WBS values than the SP but did not differ (P > .05) from the TB muscle. Electrical stimulation had no effect on WBS or any trained sensory panel values (P > .05). The percentage of loin chops rated slightly tender or better was improved 30 to 34% by electrical stimulation (P < .05). The ML muscle was scored lower (P < .05) in sustained juiciness compared with the SM, SP, and TB but did not differ (P > .05) from the ST muscle. The SM and ML muscles were rated lower (P < .05) in initial and sustained tenderness scores than other muscles. Tenderness scores were higher (P < .05) for the TB than for the SP but did not differ (P > .05) from the ST muscle. Electrically stimulating callipyge carcasses improves the tenderness of loin chops by increasing the percentage of chops rated from slightly tough to slightly tender.
本研究的目的是确定电刺激（ES）对12只汉普夏×兰布耶臀肌肥大羔羊肌肉品质和感官特性的影响。每具胴体的一侧被随机分配接受550伏、60赫兹的电刺激处理，通电2秒、断电2秒，共进行15次。另一侧为未刺激的对照（NES）。在半腱肌（ST）、半膜肌（SM）、背最长肌（ML）、冈上肌（SP）和肱三头肌（TB）上测量热稳定钙蛋白酶抑制蛋白、肌节长度、肌原纤维断裂指数（MFI）、沃纳-布拉茨勒剪切力（WBS）以及经过训练的感官评定小组的评分。对胴体两侧进行电刺激会使背最长肌的pH值下降更快（P = 0.001），且电刺激侧的腰眼肉红色比未刺激侧更亮（P = 0.001）。在储存第14天（2℃）时，TB的MFI值最高（P < 0.05），表明蛋白质降解更多，而ST和ML肌肉的MFI最低（P = 0.008）。无论电刺激处理如何，SM和ML的WBS值最高（P < 0.05）。ST肌肉的WBS值高于SP（P < 0.05），但与TB肌肉无差异（P > 0.05）。电刺激对WBS或任何经过训练的感官评定小组评分均无影响（P > 0.05）。电刺激使评定为稍嫩或更嫩的腰肉排百分比提高了30%至34%（P < 0.05）。与SM、SP和TB相比，ML肌肉在持续多汁性方面得分较低（P < 0.05），但与ST肌肉无差异（P > 0.05）。SM和ML肌肉在初始和持续嫩度评分方面低于其他肌肉（P < 0.05）。TB的嫩度评分高于SP（P < 0.05），但与ST肌肉无差异（P > 0.05）。对臀肌肥大胴体进行电刺激可通过提高评定为从稍硬到稍嫩的肉排百分比来改善腰肉排的嫩度。
