VTT Biotechnology, P.O. Box 1500, FIN-02044 VTT, Finland.
J Food Prot. 2005 Aug;68(8):1641-7. doi: 10.4315/0362-028x-68.8.1641.
D- and z-values for a mixture of four Listeria monocytogenes strains originating from the roe of different fish species were determined in rainbow trout (Oncorhynchus mykiss) roe. The D60- and D63-values obtained were 1.60 and 0.44 min, respectively, and the z-value was 5.36 degrees C accordingly. In pilot-scale experiments, rainbow trout roe (100 g) was vacuum packaged into glass jars and pasteurized both at 62 and 65 degrees C for 10 min. These treatments were enough to destroy 10(8) CFU/ g of L. monocytogenes cells, which was the highest possible Listeria cell count to grow in roe. On the basis of the determined z-value and calculation of pasteurization values, these experimental pasteurizations were found to theoretically destroy at least 45 log units of L. monocytogenes cells in rainbow trout roe. In addition, these pasteurization treatments did not significantly affect the sensory quality of the roe. The sensory quality of pasteurized vacuum-packaged rainbow trout roe stored at 3 degrees C was evaluated as good after 6 months of storage and not statistically different from the control that was frozen from the same roe lot as the pasteurized roe samples. Pasteurization of rainbow trout roe was proven to be an appropriate method for ensuring product safety with regard to L. monocytogenes and to stabilizing the sensory and microbial quality of roe. However, the safety risk caused by spore-forming bacteria still exists in pasteurized roe. Therefore, it has to be stored below 3 degrees C.
在虹鳟鱼鱼卵中测定了源自不同鱼类鱼卵的四种单增李斯特菌菌株混合物的 D 和 z 值。获得的 D60 和 D63 值分别为 1.60 和 0.44 分钟，相应的 z 值为 5.36°C。在中试规模的实验中，将虹鳟鱼鱼卵（100 克）真空包装在玻璃罐中，并在 62 和 65°C 下巴氏杀菌 10 分钟。这些处理足以破坏 10（8）CFU/g 的单增李斯特菌细胞，这是鱼卵中可能生长的最高李斯特菌细胞数。基于确定的 z 值和巴氏杀菌值的计算，这些实验巴氏杀菌理论上可以在虹鳟鱼鱼卵中至少破坏 45 个对数单位的单增李斯特菌细胞。此外，这些巴氏杀菌处理并未显著影响鱼卵的感官质量。在 3°C 下储存 6 个月后，巴氏杀菌真空包装的虹鳟鱼鱼卵的感官质量被评估为良好，与从同一批鱼卵中冷冻的对照组相比没有统计学差异，对照组与巴氏杀菌鱼卵样品来自同一批鱼卵。事实证明，巴氏杀菌是确保虹鳟鱼鱼卵中单增李斯特菌安全并稳定鱼卵感官和微生物质量的合适方法。然而，巴氏杀菌鱼卵中仍然存在形成孢子的细菌带来的安全风险。因此，它必须储存在 3°C 以下。
