Zapico P, Medina M, Gaya P, Nuñez M
Departamento de Tecnología de Alimentos, INIA, Madrid, Spain.
Int J Food Microbiol. 1998 Mar 3;40(1-2):35-42. doi: 10.1016/s0168-1605(98)00008-7.
Nisin added at 10 or 100 IU/ml to ultra-high temperature processed (UHT) skim milk had no effect on counts of Listeria monocytogenes after 24 h at 30 degrees C, whereas addition of the lactoperoxidase system (LPS) resulted in counts of viable cells three log units lower than those of control milk after 24 h at 30 degrees C. Addition of nisin and LPS showed a synergistic effect and resulted in counts up to 5.6 log units lower than the control milk. When the two preservatives were added to actively growing cells of L. monocytogenes in two steps with a 2 h interval, their synergistic effect was enhanced. Counts of L. monocytogenes Ohio after 24 h at 30 degrees C in milk with nisin and LPS added together after 3 h of growth were 5.7 log units lower than the control milk. The difference in counts increased to 7.4 log units if LPS was added after 3 h and nisin after 5 h of growth. Similar but less pronounced effects were observed for the more resistant strain L. monocytogenes Scott A.
在超高温处理（UHT）的脱脂牛奶中添加10或100国际单位/毫升的乳链菌肽，在30℃下培养24小时后，对单核细胞增生李斯特菌的数量没有影响；而添加乳过氧化物酶系统（LPS），在30℃下培养24小时后，活菌数量比对照牛奶低三个对数单位。同时添加乳链菌肽和LPS显示出协同效应，活菌数量比对照牛奶低达5.6个对数单位。当将这两种防腐剂分两步添加到处于活跃生长状态的单核细胞增生李斯特菌细胞中，间隔2小时，它们的协同效应增强。在生长3小时后同时添加乳链菌肽和LPS的牛奶中，单核细胞增生李斯特菌俄亥俄株在30℃下培养24小时后的数量比对照牛奶低5.7个对数单位。如果在生长5小时后添加乳链菌肽，在生长3小时后添加LPS，则数量差异增加到7.4个对数单位。对于更具抗性的菌株单核细胞增生李斯特菌斯科特A，观察到了类似但不太明显的效果。
