Department of Food and Animal Biotechnology, School of Agricultural Biotechnology, Center for Food and Bioconvergence, and Research Institute for Agricultural and Life Science, Seoul National University, San 56-1, Sillim-dong, Kwanak-gu, Seoul 151-742, Republic of Korea; Department of Food Science and Technology, College of Agriculture and Life Sciences, Chonbuk National University, Jeonju, Republic of Korea.
Department of Food Science and Technology, College of Agriculture and Life Sciences, Chonbuk National University, Jeonju, Republic of Korea.
Int J Food Microbiol. 2014 Feb 3;171:147-53. doi: 10.1016/j.ijfoodmicro.2013.11.001. Epub 2013 Nov 10.
We investigated the combination effect of ozone and heat treatments in apple juice for the inactivation of Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes. Apple juices inoculated with the three pathogens were treated with gaseous ozone and heat simultaneously for up to 1 min. Gaseous ozone treatment was progressed at a flow rate of 3.0 l/min with a concentration of 2.0-3.0 g/m³ and heat treatment was performed at temperatures of 25, 45, 50, and 55 °C. Populations of surviving pathogens decreased in all samples as treatment temperature increased from 25 to 55 °C. Heat treatment alone (25, 45, 50 and 55 °C) resulted in 0.20, 0.37, 2.16 and 2.54 log CFU/ml reductions of E. coli O157:H7, respectively, in apple juice. Combination treatment of ozone and heat for 1 min reduced this pathogen by 1.50 and 1.60 log CFU/ml, respectively, at 25 and 45 °C, and below the detection limit (1 log CFU/ml) at 50 and 55 °C. We found a synergistic effect in the inactivation of pathogens in apple juice treated with ozone and heated at 50 °C. The reduction trend of S. Typhimurium and L. monocytogenes in apple juice was similar to that of E. coli O157:H7. There were no significant changes of Hunter color values when apple juices were treated with heat only and the combination of ozone and heat. Residual ozone was measured following ozone treatment. In all ozone treated samples, the concentration of residual ozone was reduced to under acceptable levels (<0.4 mg/l). In conclusion, the combination treatment of ozone and heat was significantly effective in the inactivation of foodborne pathogens while maintaining acceptable apple juice quality.
我们研究了臭氧和热联合处理对苹果汁中大肠杆菌 O157:H7、肠炎沙门氏菌和单核细胞增生李斯特菌的灭活效果。将三种病原体接种到苹果汁中，然后对其进行同时的气体臭氧和热处理，处理时间长达 1 分钟。气体臭氧处理在流速为 3.0 升/分钟的条件下进行，臭氧浓度为 2.0-3.0 g/m³，热处理在 25、45、50 和 55°C 的温度下进行。随着处理温度从 25°C 升高到 55°C，所有样品中存活病原体的数量都减少了。单独的热处理（25、45、50 和 55°C）分别使苹果汁中大肠杆菌 O157:H7减少了 0.20、0.37、2.16 和 2.54 log CFU/ml。在 25 和 45°C 下，臭氧和热联合处理 1 分钟可使该病原体分别减少 1.50 和 1.60 log CFU/ml，而在 50 和 55°C 下则低于检测限（1 log CFU/ml）。我们发现，在 50°C 下用臭氧处理和加热处理的苹果汁中，病原体的失活具有协同作用。苹果汁中肠炎沙门氏菌和单核细胞增生李斯特菌的减少趋势与大肠杆菌 O157:H7 的减少趋势相似。仅进行热处理和臭氧与热联合处理时，苹果汁的亨特颜色值没有明显变化。臭氧处理后测量了残留臭氧。在所有臭氧处理的样品中，残留臭氧的浓度均降低到可接受水平（<0.4 mg/l）以下。总之，臭氧和热联合处理在保持可接受的苹果汁质量的同时，对食源性病原体的灭活非常有效。
