Takahashi Hajime, Komori Kaori, Nakamura Ayaka, Koike Fumiaki, Kuda Takashi, Iwamoto Makoto, Onodera Jin, Mizowaki Jitsuo, Kobayashi Mitsushi
Tokyo University of Marine Science and Technology.
Hida Meat Agricultural Cooperative Association.
Shokuhin Eiseigaku Zasshi. 2025;66(3):39-45. doi: 10.3358/shokueishi.66.39.
Peracetic acid formulation has received much attention in recent years as a surface disinfectant for beef. There are many reports on the bactericidal effect of peracetic acid formulation on beef surfaces. However, the application method of peracetic acid formulation aiming at the complete removal of Shiga toxin-producing Escherichia coli (STEC) from the surface of sub-primal cuts has not been evaluated. The objective of this study was to determine the condition under which peracetic acid formulation can be used to completely remove STEC from the surface of sub-primal cuts of beef.The effect of peracetic acid formulation was evaluated by immersing pieces of beef on whose surfaces E. coli O157:H7 were inoculated. To investigate the impact of peracetic acid concentration on bactericidal efficacy, small pieces (5 cm×5 cm×5 cm) of meat from five parts were immersed in peracetic acid at concentrations of 900 ppm and 1800 ppm for 30 min. The bacterial counts were decreased by 2.6-4.0 log CFU/cm at 900 ppm, indicating a varying bactericidal effect depending on parts of beef. Conversely, at 1800 ppm, declines of 3.9-4.1 log CFU/cm were observed, reaching the detection limit. To confirm the efficacy of peracetic acid formulation on the surface of sub-primal cuts, larger pieces (5 cm×20 cm×20 cm) of beef from nine parts were immersed in 1800 ppm peracetic acid for 30 min. As was the case with small pieces of beef, bacterial counts were decreased by 3.5-3.8 log CFU/cm and reached the detection limit. Given the actual number of total viable bacteria on the surface of sub-primal cuts, the reduction in bacterial counts observed in this study is a condition that allows for complete removal of STEC from the surface of sub-primal cuts.Consequently, it can be concluded that the immersion in peracetic acid with a concentration of 1800 ppm for 30 min is the appropriate treatment to decontaminate STEC totally from the surface of sub-primal cuts of beef.
近年来，过氧乙酸制剂作为牛肉的表面消毒剂受到了广泛关注。关于过氧乙酸制剂对牛肉表面的杀菌效果已有许多报道。然而，针对从牛肉分割切块表面完全去除产志贺毒素大肠杆菌（STEC）的过氧乙酸制剂应用方法尚未得到评估。本研究的目的是确定过氧乙酸制剂可用于从牛肉分割切块表面完全去除STEC的条件。通过将接种了大肠杆菌O157:H7的牛肉片浸泡来评估过氧乙酸制剂的效果。为研究过氧乙酸浓度对杀菌效果的影响，将来自五个部位的小块（5厘米×5厘米×5厘米）肉分别浸泡在浓度为900 ppm和1800 ppm的过氧乙酸中30分钟。在900 ppm时，细菌计数下降了2.6 - 4.0 log CFU/平方厘米，表明杀菌效果因牛肉部位而异。相反，在1800 ppm时，观察到细菌计数下降了3.9 - 4.1 log CFU/平方厘米，达到检测限。为确认过氧乙酸制剂对牛肉分割切块表面的效果，将来自九个部位的较大块（5厘米×20厘米×20厘米）牛肉浸泡在1800 ppm过氧乙酸中30分钟。与小块牛肉的情况一样，细菌计数下降了3.5 - 3.8 log CFU/平方厘米并达到检测限。鉴于牛肉分割切块表面的实际总活菌数，本研究中观察到的细菌计数减少是能够从牛肉分割切块表面完全去除STEC的条件。因此，可以得出结论，将牛肉分割切块浸泡在浓度为1800 ppm的过氧乙酸中30分钟是从牛肉分割切块表面完全去除STEC的适当处理方法。
