糖盐介质中γ-射线辐照对英诺克李斯特菌的杀菌效果研究

Theγ-Irradiation Sterilization Effect on Listeria Innocua in Sugar and Salt Medium

为研究食品基质对γ-辐照杀菌效果的影响,本试验以英诺克李斯特菌(Listeria Innocua)为试材,采用lgN-D线性回归分析,建立活菌数-剂量的拟合方程,获得D_(10)值;利用D_(10)值表征无菌水环境下γ-射线和电子束辐照的吸收剂量差异,以及不同γ-射线吸收剂量、糖浓度、盐浓度对英诺克李斯特菌杀菌效果的影响。结果表明,当辐照在无菌水液体环境下时,γ-射线的D_(10)值均小于电子束,分别为0.788和0.872 kGy,表明γ-射线的杀菌效果更好;在γ-射线辐照下,杀灭生理盐水(0.85%NaCl)中英诺克李斯特菌的D_(10)值与无菌水无明显差别,随着盐浓度的增加,D_(10)值呈先增加后减少的趋势,其中在3%和5%盐浓度下的D_(10)值分别为0.709和0.730 kGy,明显低于无菌水组;杀灭糖溶液中英诺克李斯特菌的D_(10)值明显高于无菌水组,随着糖浓度的增加,D_(10)值先升高后降低,其中5%糖溶液的D_(10)值最大,为1.133 kGy。说明盐溶液对杀菌有协同作用,而糖溶液对杀菌有抵抗作用。本研究结果为进一步探索辐照杀菌机制,降低辐照剂量成本,提升产品品质提供了一定的参考。

In order to know the effect of food matrix on the sterilization efficacy ofγ-irradiation.By lgN-D linear regression analysis,the formula of the number of viable bacteria was obtained.The D_(10)value was used to characterize the difference of absorbed dose of gamma ray and electron beam irradiation in sterile water environment,and the influence of different gamma ray absorption dose,sugar concentration and salt solution concentration on the germicidal efficacy of Listeria Innocua was analyzed.The results shows that when the irradiation environment is the sterile water,the gamma ray D_(10)value is less than the electron beam,respectively 0.788 and 0.872 kGy,which shows that the gamma ray sterilization effect is better.Under the irradiation of gamma ray,The D_(10)value of Listeria Innocua in sterilized saline(0.85%NaCI)was not significantly different from that of sterile water.With the increase of salt concentration,the D_(10)value of innocua first increased and then decreased,and the D_(10)value at 3%and 5%salt concentration was 0.709 kGy and 0.730 kGy,respectively,lower than that of sterile water.The D_(10)value of Listeria Innocua in sugar solution was significantly higher than that of sterile water.With the increase of the concentration of sugar solution,D_(10)first increased and then decreased.The D_(10)value of 5%sugar solution was the largest,which was 1.13 kGy.It could be seen that salt solution has a synergistic effect on sterilization,while sugar solution has a resistance effect on sterilization.The results provide a reference for further exploring the mechanism of irradiation sterilization,reducing radiation dose cost and improving product quality.