包装内O_2对冷却肉微生物生长的影响

研究了气调包装内不同初始氧浓度对冷却肉微生物生长的影响。来自冷却猪肉的混合微生物群接种于液体培养基中,经不同O2浓度的无CO2气调包装后于3℃下贮藏,测定其中假单胞菌属、肠杆菌科及乳酸菌的生长变化,同时测定样品中菌落总数的变化规律。采用Baranyi模型拟合微生物生长变化数据得到相关动力学参数。结果表明:包装内初始O2浓度在11.0%～79.0%范围内变化时,3种特征微生物生长及菌落总数的变化均不受影响;0.3%～11.0%范围内,初始氧浓度的降低可不同程度上抑制假单胞菌属、肠杆菌科及乳酸菌的生长,且浓度越低,抑制作用越强;同时,低氧浓度也能有效抑制混合菌群菌落总数增长。

Effect of concentration of O2 concentration in packaging on the growth of microorganism from chilled meat

The effect of different initial concentrations of O2 in modified atmosphere packaging on the growth of microorganism from chilled meat was investigated.The mixed strains from chilled pork were inoculated into the liquid medium which were packaged with different concentrations of O2.The samples were stored at 3℃ and the number of Pseudomonas,Enterobacteriaceae,Lactic acid bacteria and total number colonies were collected at different time during the storage.The results demonstrated that the initial concentration of O2 showed little influence on these microorganism when it was changed from 11.0% to 79.0%.And the low concentration of O2(0.3%～11.0%) could effectively curbed the growth of the microorganism,the lower the concentration the heavier the inhibition.The order of the inhibition effect from the strongest to the weakest was total number colonies,E.coli,Lactic acid bacteria and Pseudomonas.