Center for Food Safety, Department of Animal Science, Texas AgriLife Research, Texas A&M University, College Station, TX 77843-2471, USA.
J Food Prot. 2012 Apr;75(4):682-9. doi: 10.4315/0362-028X.JFP-11-409.
The effect of heating rate on the heat resistance, germination, and outgrowth of Clostridium perfringens spores during cooking of cured ground pork was investigated. Inoculated cured ground pork portions were heated from 20 to 75°C at a rate of 4, 8, or 12°C/h and then held at 75°C for 48 h. No significant differences (P > 0.05) in the heat resistance of C. perfringens spores were observed in cured ground pork heated at 4, 8, or 12°C/h. At heating rates of 8 and 12°C/h, no significant differences in the germination and outgrowth of spores were observed (P > 0.05). However, when pork was heated at 4°C/h, growth of C. perfringens occurred when the temperature of the product was between 44 and 56°C. In another set of experiments, the behavior of C. perfringens spores under temperature abuse conditions was studied in cured and noncured ground pork heated at 4°C/h and then cooled from 54.4 to 7.2°C within 20 h. Temperature abuse during cooling of noncured ground pork resulted in a 2.8-log CFU/g increase in C. perfringens. In cured ground pork, C. perfringens decreased by 1.1 log CFU/g during cooling from 54.4 to 36.3°C and then increased by 0.9 log CFU/g until the product reached 7.2°C. Even when the initial level of C. perfringens spores in cured ground pork was 5 log CFU/g, the final counts after abusive cooling did not exceed 3.4 log CFU/g. These results suggest that there is no risk associated with C. perfringens in cured pork products under the tested conditions.
加热速率对腌制绞碎猪肉烹饪过程中梭菌耐热性、发芽和生长的影响。将接种的腌制绞碎猪肉部分以 4°C/h、8°C/h 或 12°C/h 的速率从 20°C 加热至 75°C，然后在 75°C 下保持 48 h。以 4°C/h、8°C/h 或 12°C/h 加热时，未观察到梭菌耐热性有显著差异（P＞0.05）。在 8°C/h 和 12°C/h 的加热速率下，未观察到孢子发芽和生长有显著差异（P＞0.05）。然而，当猪肉以 4°C/h 的速率加热时，当产品温度在 44°C 至 56°C 之间时，梭菌会生长。在另一组实验中，研究了在 4°C/h 加热然后在 20 h 内从 54.4°C 冷却至 7.2°C 的腌制和未腌制绞碎猪肉中梭菌孢子在温度滥用条件下的行为。在未腌制绞碎猪肉的冷却过程中滥用温度会导致梭菌增加 2.8-log CFU/g。在腌制绞碎猪肉中，梭菌从 54.4°C 冷却至 36.3°C 时减少了 1.1-log CFU/g，然后在产品达到 7.2°C 之前增加了 0.9-log CFU/g。即使腌制绞碎猪肉中梭菌孢子的初始水平为 5-log CFU/g，滥用冷却后的最终计数也不会超过 3.4-log CFU/g。这些结果表明，在所测试的条件下，腌制猪肉产品中不存在与梭菌相关的风险。
