高压力杀灭大肠杆菌的研究

STUDY ON THE DEATH OF ESCHERICHIA COII INDUCED BY HYDROSTATIC PRESSURES

除传统的加热杀菌及辐照保鲜食品技术外,目前国外正在研究高压力(hydrostatic pressure)食品加工法。食品经此法处理后,可杀死绝大多数细菌,且仍能保持食品新鲜及原味,不会破坏其营养成分。这项技术已被国外列为10大关键科技之一。近来,作者以大肠杆菌为模型,研究了高压力的大小、施压时间及施压时的温度对其存活率的影响。 1 材料和方法 1.1 材料 1.1.1 菌株:大肠杆菌(Escherichiacoli No.44156)购自上海市卫生防疫站菌种室。 1.1.2 仪器:高压力设备按Paladini和Weber的设计,作者自行研制,可产生1～2500bar压力。 1.1.3 LB培养基(％):胰蛋白胨1,酵母抽提粉0.5,NaCll,pH 7.5,琼脂1.5。

The effect of hydrostatic pressure on the death of E. coli was studied in this paper. The results indicated that E. coli could be killed by hydrostatic pressure above 800 bar. At 2300 bar E.coli was totally killed in 30 minutes. The time course of E. coli death induced by pressure indicated that the most E. coli was killed in the first 10 minutes after the pressure was applied. It was also found that the lower temperature favored killing E. coli under pressure.