摘要
利用脉冲磁场对大肠杆菌、金黄色葡萄球菌、酿酒酵母和枯草芽孢杆菌在不同介质温度、pH、初始菌落数和Na+浓度等的情况下进行杀菌试验,结果表明:介质温度越高,脉冲磁场杀菌效果越好,但该温度远低于热致死温度;介质pH越偏中性,杀菌效果越差,pH值小于5时,杀菌效果较好;微生物残留率随着Na+浓度的升高而降低,Na+浓度越高,杀菌效果越好;微生物残留率随着初始菌落数的增大而下降,初始菌落数越高,杀菌效果越好;菌种不同,残留率不同,酿酒酵母的残留率最低,枯草芽孢杆菌的残留率最高;酿酒酵母的残留率随着葡萄糖和乳糖含量的增大而上升,含量越大,杀菌效果越差;酿酒酵母残留率随着乙醇含量的增大而下降,含量越大,杀菌效果越好;酿酒酵母残留率随着蛋白胨含量的增大而上升,含量越大,杀菌效果越差;酿酒酵母残留率随着干酪素含量的增大而下降,含量越大,杀菌效果越好。
The effects of medium parameters such as temperature, pH and initial number of microorganism on the inactivationof Escherichia coli, Staphylococcus aureus, Saccharaomyces cerevisiae & Bacillus subtilis subjected to pulsed magnetic fields wasstudied. Results showed: The survival rate of microorganism ran down with an increase in temperature. Furthermore, thetemperatures employed in the present study were far below pasteurization temperature. The survival rate was maximum at pHfrom 6 to 7, while the bactericidal effect became better with pH less than 5. The survival rate of microorganism ran down withan increase in the concentration of Na+. The higher the concentration of Na+ was, the better the bactericidal effect. The survivalrate of microorganism ran down with an increase in the initial number of microorganism. The higher the initial number ofmicroorganism was the better the bactericidal effect. The bactericidal effect was different to different species of microorganism.As a whole, the survival rate of S.cerevisiae was low while, the survival rate of B.subtilis was high. The survival rate of S.cerevisiaeran up with an increase in the content of dextrose or lactose. The higher the content of dextrose or lactose was, the poorer thebactericidal effect. The survival rate of S.cerevisiae ran down with an increase in the content of alcohol. The higher content ofalcohol was, the better the bactericidal effect. The survival rate of S.cerevisiae ran up with an increase in the content of peptone.The higher the content of peptone was, the poorer the bactericidal effect. The survival rate of S.cerevisiae ran down with an increasein the content of casein. The higher the content of casein was, the better the bactericidal effect.
出处
《食品科学》
EI
CAS
CSCD
北大核心
2004年第8期42-46,共5页
Food Science
基金
江苏省教育厅"青蓝工程"跨世纪学术带头人基金项目