Castañeda M P, Hirschler E M, Sams A R
Department of Poultry Science Texas A&M University College Station, Texas 77843-2472, USA.
Poult Sci. 2005 Mar;84(3):479-81. doi: 10.1093/ps/84.3.479.
Postmortem electrical stimulation (ES) tenderizes meat by acceleration of adenosine triphosphate (ATP) depletion, pH decline, and physical disruption of muscle fibers. It has been demonstrated that rigor development at elevated temperatures, as with slow chilling, can cause meat to develop pale color and poor water-holding capacity. The objective of this study was to compare the functionality of broiler breast meat from control and electrically stimulated carcasses with and without normal rapid chilling. Broilers were either electrically stimulated (450 mA, 450 V, 2 s on, 2 s off for 7 pulses) immediately after bleeding or used as nonstimulated controls. The ES birds were either chilled immediately (ES2) or had chilling delayed for 2 h at room temperature (ESD2). All ES breast fillets were harvested at 2 h postmortem. The control carcasses were chilled immediately and had fillets harvested at 2 h postmortem (C2) or at 8 h postmortem (C8). Electrical stimulation accelerated pH decline and prevented toughening when breast meat was deboned at 2 h postmortem, regardless of chilling rate. The water released from the gels during cooking was higher for the ESD2 than the ES2 group, which was not different from the C2 group, suggesting that ES followed by slow chilling reduced water-holding capacity compared with the ES2 and C2 groups. There were no differences in expressible moisture, gel strength, or lightness among the ES2, ESD2, and C2 treatments. These results indicated that high voltage ES followed by normal chilling did not impair protein functionality or cause pale, soft, exudative meat. However, there was some evidence that slow chilling after ES may negatively affect some water-holding properties of the meat.
宰后电刺激(ES)通过加速三磷酸腺苷(ATP)消耗、pH值下降以及肌肉纤维的物理破坏来使肉嫩化。已经证明,与缓慢冷却一样,在高温下僵直发展会导致肉颜色变浅和保水性变差。本研究的目的是比较来自对照和电刺激屠体的鸡胸肉在有无正常快速冷却情况下的功能。肉鸡在放血后立即进行电刺激(450毫安、450伏、开2秒、关2秒,共7个脉冲)或用作非刺激对照。电刺激的鸡要么立即冷却(ES2),要么在室温下延迟冷却2小时(ESD2)。所有电刺激的胸肉在宰后2小时采集。对照屠体立即冷却,并在宰后2小时(C2)或宰后8小时(C8)采集胸肉。无论冷却速度如何,电刺激都能加速pH值下降,并在宰后2小时去骨时防止鸡胸肉变硬。ESD2组在烹饪过程中从凝胶中释放的水分高于ES2组,ESD2组与C2组没有差异,这表明与ES2组和C2组相比,电刺激后缓慢冷却会降低保水性。ES2、ESD2和C2处理组之间在可表达水分、凝胶强度或亮度方面没有差异。这些结果表明,高压电刺激后正常冷却不会损害蛋白质功能,也不会导致肉色苍白、质地柔软、渗出性强。然而,有一些证据表明,电刺激后缓慢冷却可能会对肉的一些保水特性产生负面影响。