Key Laboratory of Meat Processing and Quality Control, MOE, College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, PR China.
Meat Sci. 2013 Apr;93(4):865-72. doi: 10.1016/j.meatsci.2012.11.053. Epub 2012 Dec 13.
Pre-slaughter fasting is a very important practice in the meat industry. The present study was designed to investigate the effect of fasting on energy metabolism and tenderizing enzymes in chicken muscle early postmortem. A total of 30 Yellow-feathered chickens were deprived of feed for 0 h, 12 h and 24 h before slaughter (n=10 each group). Breast muscles were removed and cut into 3 parts and stored at 0°C for 0 h, 3 h and 10 h. Samples were used for analyses of zymography, cathepsins, pH, glycogen/ATP/ADP/AMP, hormones and ultrastructure. Fasting caused the accelerated depletion (p<0.05) of glycogen, ATP and ADP before or immediately after slaughter, but no difference existed in ATP at 3 and 10 h (p>0.05). Fasting resulted in greater ultimate pH (p<0.05). Zymography indicated that fasting delayed the activation of μ/m-calpain (p<0.05), however, it accelerated the release of lysosomal enzymes (p<0.05). Fasting for 24 h resulted in greater ultrastructural changes and plasma corticosterone levels than fasting for 12 h and control groups. Therefore, fasting for no more than 12 h is acceptable in practice.
宰前禁食是肉类行业中非常重要的做法。本研究旨在探讨宰前禁食对鸡肉宰后早期能量代谢和嫩化酶的影响。将 30 只黄羽鸡禁食 0、12 和 24 h（每组 10 只），然后屠宰。取胸肌并切成 3 部分，在 0°C 下储存 0、3 和 10 h。对样品进行酶谱分析、组织蛋白酶、pH 值、糖原/ATP/ADP/AMP、激素和超微结构分析。禁食导致宰前或宰后即刻糖原、ATP 和 ADP 迅速耗竭（p<0.05），但 3 和 10 h 时 ATP 无差异（p>0.05）。禁食导致最终 pH 值更高（p<0.05）。酶谱分析表明，禁食延迟了 μ/m-钙蛋白酶的激活（p<0.05），但加速了溶酶体酶的释放（p<0.05）。禁食 24 h 比禁食 12 h 和对照组导致更大的超微结构变化和血浆皮质酮水平。因此，在实际操作中，禁食时间不超过 12 h 是可以接受的。
