宰后猪肌肉糖酵解与肉质性状的相关性分析

Correlation analysis between postmortem glycolysis and meat quality traits in pigs

为了研究宰后猪肌肉糖酵解对肉质性状的影响,试验选择48头北京黑猪对其肉质性状[宰后24 h的pH值、肉色L~*值、72 h滴水损失(DL值)]以及糖酵解指标[宰后6 h及24 h的丙酮酸激酶(PK)、乳酸脱氢酶(LDH)活性和丙酮酸(PA)、乳酸(LA)含量]进行测定,并对肉质性状及糖酵解指标进行Pearson相关分析。结果表明:宰后24 h pH值为5.94,24 h L~*值为50.61,72 h DL值为1.41;24 h pH值与24 h L~*值、72 h DL值均呈极显著负相关(P<0.01),24 h L~*值与72 h DL值呈极显著正相关(P<0.01)。宰后24 h的PK、LDH活性极显著低于宰后6 h(P<0.01);宰后6 h LDH活性与宰后6 h、24 h LA含量均呈显著正相关(P<0.05);宰后6 h LA含量以及LDH活性与72 h DL值呈显著或极显著正相关(P<0.05或P<0.01),与24 h pH值呈极显著负相关(P<0.01),分别与24 h L~*值呈极显著或显著正相关(P<0.01或P<0.05)。说明LDH活性对于宰后肌肉糖酵解具有更为重要的调控作用,其活性与LA的含量及肉质性状密切相关,LDH活性与LA含量可作为肉质性状评价的指标。

In order to study the effect of postmortem glycolysis on meat quality traits, a total of 48 Beijing black pigs were sacrificed and the Pearson correlation analyses were performed between the meat quality traits(24 h pH, 24 h L~*, and 72 h drip loss(DL)) and the glycolysis related enzymes and metabolites(6 and 24 h pyruvate kinase(PK) activity, lactate dehydrogenase(LDH) activity, pyruvate concentration and lactate concentration). The results showed that the 24 h pH, 24 h L~*, and 72 h DL were 5.94, 50.61, and 1.41, respectively. The 24 h pH showed extremely significant negative correlation with both the 24 h L~* and the 72 h DL(P< 0.01). The 24 h L~* showed extremely significant positive correlation with 72 h DL(P<0.01). The activities of PK and LDH in 24 h were lower than those in 6 h(P<0.01). The 6 h LDH activity was significant positively associated with lactate concentration either in 6 or 24 h(P<0.05). The 6 h lactate concentration and LDH activity had significant or extremely significant positive correlation with 72 h DL(P<0.05 or P<0.01), and extremely significant negative correlation with the 24 h pH(P< 0.01). The 24 h L~* had extremely significant positive correlation with the 6 h lactate concentration(P<0.01), and significant positive correlation with the 6 h LDH activities(P<0.05). In conclusion, this study suggested that LDH might have a important role in the regulation of muscle glycolysis after slaughter and was closely related to lactate concentration and meat quality. The LDH activity and lactate concentration could be used to evaluate the meat quality.