介质参数对脉冲磁场杀灭枯草芽孢杆菌的影响  

Influence of medium parameters on pulsed magnetic fields inactivation of Bacillus Subtilis

作　　者：钱静亚[1,2] 陈超[3] 王晨燕[3] 马海乐[1,2] 李树君[1,4] 

机构地区：[1]江苏大学食品与生物工程学院,江苏镇江212013 [2]江苏省农产品生物加工与分离工程技术研究中心,江苏镇江212013 [3]江苏大学京江学院,江苏镇江212013 [4]中国农业机械化科学研究院,北京100083

出　　处：《食品与机械》2012年第5期8-11,共4页Food and Machinery

基　　金：国家"863"计划重点项目(编号:2007AA100405)

摘　　要：利用脉冲磁场设备对枯草芽孢杆菌进行杀菌试验,研究介质温度、pH和水分活度对其杀菌效果的影响。采用倾注平板计数法对杀菌结果进行检查。结果表明:低温或较高温对脉冲磁场的杀菌作用具有促进作用,酸性或碱性介质也促进了脉冲磁场的杀菌作用,水分活度越低,杀菌作用越强。采用磁场强度为3.0T,脉冲数为30的脉冲磁场进行杀菌,介质温度为5℃时,枯草芽孢杆菌的残留率最低为19.15%;介质pH为4.5时,残留率最低为3.00%;介质水分活度为0.88时,残留率最低为3.14%。通过透射电镜观测,磁场可能破坏了枯草芽孢杆菌的细胞膜结构,而较高温度的酸性介质有可能增强破坏作用。低温或较高温、低pH、低水分活度的介质可以提高脉冲磁场的杀菌效果。Effect of temperature,pH,water activity in medium on inactivation of Bacillus Subtilis by pulsed magnetic field were investigated.Pour plate counting method was used to test inactivation result.Result showed that low and higher temperature,and acidic or alkaline medium all increased the inactivation influence of pulsed magnetic field.The lower water activity,the stronger inactivation effect on Bacillus Subtilis.When magnetic field intensity was 3.0 T and pulse number was 30,the survival rate reached to minimum value of 19.15%,3.00% and 3.14% at temperature of 5℃,pH value of 4.5 and water activity of 0.88,respectively.Transmission electron microscope observation indicated that pulsed magnetic field may destroyed the cell membrane and acidic medium with higher temperature strengthened the damage.Conclusion： Medium with low or higher temperature,low pH,and low water activity has improved inactivation effect by pulsed magnetic field.

关 键 词：脉冲磁场 枯草芽孢杆菌 杀菌 温度 PH 水分活度 透射电镜 

分 类 号：TS205.9[轻工技术与工程—食品科学]