腌制温度对羊肉蛋白质磷酸化水平的影响

Effect of Salting Temperature on the Protein Phosphorylation of Mutton

摘要:

研究了不同腌制温度对羊肉肌原纤维蛋白和肌浆蛋白磷酸化水平的影响。取宰后排酸24 h的胴体米龙，设定-1 ℃、4 ℃和25 ℃三个腌制处理组，取腌制0 h、8 h、16 h和24 h的样品，采用SDS-PAGE电泳与荧光染色相结合的方法分析磷酸化水平的变化。结果表明，腌制温度越低，肌原纤维蛋白整体磷酸化水平（P/T值）越高，腌制8 h时，冰温组整体磷酸化水平显著高于室温组（p<0.05），腌制16 h和24 h时无显著差异。而肌浆蛋白磷酸化水平结果与之相反，腌制温度越低，肌浆蛋白质整体磷酸化水平越低。腌制8 h时，冰温腌制组整体磷酸化水平显著低于室温腌制组（p<0.05），腌制16 h和24 h时也无显著差异。单个蛋白条带呈现差异，随着腌制温度的升高，肌动蛋白和醛缩酶磷酸化水平升高，肌球蛋白和烯醇酶磷酸化水平降低。因此，腌制温度可能通过影响蛋白质磷酸化，进而调控肉的品质。

Abstract:

The effect of different salting temperatures on the phosphorylation level of myofibrillar and sarcoplasmic proteins in mutton was investigated. The topside muscles from both hind legs were removed immediately after slaughter and aged at 4 ℃ for 24 h, and then three salting treatment groups were set up at -1 ℃, 4 ℃, and 25 ℃. Samples from each group were collected at 0 h, 8 h, 16 h, and 24 h, and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) combined with fluorescence staining was employed to analyze phosphorylation levels. The results showed that the global phosphorylation level (P/T) of myofibrillar proteins increased with decreasing salting temperature. After 8 h of salting, the global phosphorylation level of the myofibrillar proteins with freezing temperature treatment was significantly higher than that of the myofibrillar proteins with room temperature treatment (p<0.05), and no significant difference was found between the samples salt-treated for 16 h and those treated for 24 h. The results of the sarcoplasmic protein phosphorylation showed the opposite trend, and the global phosphorylation level of sarcoplasmic proteins decreased with decreasing salting temperature. After 8 h of salting, the global phosphorylation level of the sarcoplasmic proteins with freezing temperature treatment was significantly lower than that of the sarcoplasmic proteins with room temperature treatment (p<0.05), and no significant difference was found between the samples salt-treated for 16 h and those treated for 24 h. The effect of salting temperature on the phosphorylation level of individual protein bands was different. The phosphorylation levels of actin and aldolase increased with increasing salting temperature, while those of myosin and enolase decreased. Therefore, salting temperature can regulate the meat quality by influencing the phosphorylation of muscle proteins.