热协同超高压处理对不同介质中芽孢发芽的影响  

Inactivation Effect Of High Pressure Combined Heating On Spores Germination In Different Medium

作　　者：武玉艳[1] 李汴生[1] 黄娟 

机构地区：[1]华南理工大学轻工与食品学院,广东广州510640 [2]广州市质量监督检测研究院,广东广州510110

出　　处：《食品研究与开发》2010年第1期138-142,共5页Food Research and Development

基　　金：国家高技术研究发展计划(863计划)重点项目(2007AA100405);广东省自然科学基金项目(05006597)

摘　　要：以磷酸缓冲液(pH=6.7)及经过凝结芽孢杆菌(BC)和嗜热脂肪芽孢(BS)杆菌人工污染的牛奶、鸡腿菇、卤牛肉为对象,分别测定压热处理后的细菌菌落总数。结果显示:在磷酸缓冲液中BC在初温为50℃时(保压5min)发芽率为2.05个数量级,BS在初温为60℃时发芽率为2.13个数量级;温度升高30℃时(保压时间10min)BC的发芽率增加了1.4个数量级,BS增加了近2个数量级而压力增加100MPa时BC发芽率增加了0.6个数量级,BS为0.27个数量级,表明初温较低的情况下较易引起芽孢发芽,在一定的压力和温度范围内温度变化30℃较压力变化100MPa对芽孢的发芽率影响明显,随着施压条件的加强(包括初温的增加、目标压力的增加),压力诱导芽孢发芽的程度也相对减小。三种食品介质中呈现出与磷酸缓冲液中相似的结果。这表明在四种酸性介质中一定的温度范围内热仍旧是促使芽孢发芽的重要因素。Phosphate buffer （pH =6.7）,milk,coprinus comaus,traditional pot-stewed meats,which were contaminated with Bacillus stearotherophilus spores or Bacillus coagulans,were treated by high pressure combined heating with different time.The aerobic plate count was determined before and after these treatments.The results showed that in phosphate buffer when the temperature was 50 ℃（pressure 5 min）the germination rate of Bacillus coagulans was 2.05 magnitude（2.05 log）and when the temperature was 60 ℃（pressure 5 min） the germination rate of Bacillus stearotherophilus was 2.13 magnitude （2.13 log）.When the temperature was increased 30 ℃,the germination rate of Bacillus coagulans increased 1.4 magnitude （1.4 log）while Bacillus stearotherophilus increased about 2 magnitude （2 log）.When the pressure was increased 100 MPa the germination rate of Bacillus coagulans increased 0.6 magnitude （0.6l0 g） while Bacillus stearotherophilus increased about 2 magnitude（2 log）.The lower termperature easy caused germination.To a certain pressure and temperature range,the affect of germination rate significant by temperature changing 30 ℃ than pressure changing 100 MPa.With strengthening pressure conditions （including early temperature and target pressure increasing）the pressure induced germination relative reduced.The three kind of food medium show a similar result with phosphate buffer.This shows that in the acid medium heat is an important factor at spore germination in a certain temperature.

关 键 词：超高压 嗜热脂肪芽孢杆菌 凝结芽孢杆菌 发芽 

分 类 号：R155.5[医药卫生—营养与食品卫生学]