摘要
本研究以蛋清液为基质,接种大肠杆菌、沙门氏菌和金黄色葡萄球菌后,比较了高密度CO2（DPCD）、高压脉冲电场（PEF）及热处理对这三种菌的杀灭效果以及对蛋清液物化性质的影响,结果表明：对于大肠杆菌和沙门氏菌,DPCD的杀菌效果最佳;热处理杀灭三种细菌达到2~3个对数值,效果优于PEF处理;未处理蛋清液货架期为2d左右,而经过DPCD、PEF和热处理杀菌后,可分别延长蛋清液的货架期至20、12、14d。DPCD、PEF和热处理也使得蛋清液的物化性质发生一定程度的变化。DPCD处理显著降低了蛋清液的pH及凝胶强度,并且使其电导率大大增加;PEF处理提高了蛋清液的黏度,降低了其凝胶强度,而热处理对其物化性质影响最大,降低了蛋清液的黏度,显著提高了其凝胶强度。
Egg white was chosen as a substrate, inoculated with E. coil, Salmonella and Staphylococcus aureus, and then compared the bactericidal effects and the changes of physicochemical properties of egg white after treated respectively by dense phase CO2 （DPCD）, pulsed electrical fields （PEF）, and thermal treatment.After the determination of relevant indicators, the conclusions could be drawn as follows. DPCD had achieved the best bactericidal effect for Ecofi and Salmonella.Thermal treatment could reduce 2 to 3 logarithm of bacteria, and the bactericidal effect was better than PEF treatment.The shelf-life of untreated egg white lasted only 2 days,while the shelf-life of egg white treated by DPCD, PEF, and thermal treatment combined with cold storage were extended to 20 days,12 days and 14 days.DPCD, PEF and heat treatment also made the physical and chemical properties of egg white change on a certain extent.The pH value and gel strength of egg white was significantly reduced by DPCD treatment,while this kind of treatment greatly increased its electrical conductivity.PEF treatment increased the viscosity of egg white, but reduced its gel strength. Compared with the fresh egg white, the effect of heat treatment on the change of physical and chemical properties was the largest, and this kind of treatment reduced the viscosity but significantly increased gel strength of egg white.
出处
《食品工业科技》
CAS
CSCD
北大核心
2014年第11期143-146,151,共5页
Science and Technology of Food Industry
基金
渤海大学博士启动基金项目(BHU201250)
