草氨酸钠抑制乳酸脱氢酶对冷却牛肉肉色稳定性的影响

Effects of Lactate dehydrogenase inhibited by oxamate on color stability of chilled beef

【目的】研究草氨酸钠抑制剂对冷却肉中乳酸脱氢酶活性(LDH)及表面肉色的影响.【方法】从牛胴体上取背最长肌,随机分成两组,一组肌肉喷射草氨酸钠,一组不做任何处理.在4℃下冷藏7d,每隔2d分别测定肉色、色素含量、pH值、NADH浓度、乳酸脱氢酶和高铁肌红蛋白还原酶活性等指标.【结果】草氨酸钠处理组a*值显著低于对照组,b*值差异不显著,L*值没有差别,总色素含量呈下降趋势.含有草氨酸钠的肌肉中LDH,NADH浓度显著降低(P<0.05),相关性分析表明LDH活性,NADH浓度及高铁肌红蛋白还原酶(MetMbR)活性之间存在显著的正相关(P<0.05).【结论】证实了草氨酸钠抑制了乳酸脱氢酶的活性,导致NADH的浓度和MetMbR活性降低,从而维持肉色的稳定性.

【Objective】The aim was to study the effect of oxamate inhibitor on lactate dehydrogenase(LDH)and the surface color stability of chilled beef.【Method】The longissimus dorsi was taken from the cow carcass and randomly divided into two groups,then one group was injected with oxamate sodium,and the other was not treated and the meat color,pigment content,pH value,NADH concentration,LDH and metmyoglobin reductase(MetMbR)activity were measured every two days during 7 days in cold storage under 4 degrees.【Result】The a*value of the treatment group was significantly lower than that of the control group,the difference in b*value was not significant,there was no difference in the L*value and the total pigment decreased.The LDH,NADH concentration in muscle with oxamate sodium decreased significantly(P<0.05).Correlation analysis showed that the LDH activity,NADH concentration and MetMbR significantly positively correlated(P<0.05).【Conclusion】Oxamate sodium inhibited the activity of lactate dehydrogenase,decreased the NADH concentration and MetMbR activity and maintained the stability ofmeat color.