阻抗法快速分析牛奶中的菌落总数  

Rapid Detection of Total Bacteria Count in Milk by the Impedance Method

作　　者：张爱萍[1] 孟瑞锋[1] 侯式娟[2] 唐佳妮[1] 刘东红[1] 

机构地区：[1]浙江大学生物系统工程与食品科学学院,杭州310029 [2]烟台大学化学生物理工学院,山东烟台264005

出　　处：《中国食品学报》2012年第2期158-164,共7页Journal of Chinese Institute Of Food Science and Technology

基　　金：十一五国家科技支撑课题(2009BADB9B06)

摘　　要：以电导、总阻抗、双电层电容、培养介质电容、阻抗角作为检测参数,比较含初始菌数不同的阻抗测试管的阻抗变化率曲线,结果阻抗角不适于作为阻抗法快速分析牛奶中菌落总数的检测参数。将检出时间DT值和平板计数法得到的菌落总数的对数值lgC用SAS做线性回归,结果电导、总阻抗、双电层电容之间存在线性相关。用Δ=lg(C0/CSPC)=lg(C0)-lg(CSPC)值分析阻抗法的检测误差,结果由电导、总阻抗作为检测参数得到的菌落总数值符合实际情况。用阻抗法快速分析牛奶中的菌落总数时,分析FPR、FNR随DTTH的变化趋势,DTTH值分别选440min(电导和总阻抗)和410min(双电层电容)。Took the conductance, the total impedance, the double-layer capacitance, the medium capacitance, the impedance angle as the examination parameter, compared and analyzed curves of change rate of these impedance parameters, obtaining that the impedance angle not be suitable for the analysis of the total bacteria count of milk. When the examination parameter was the conductance, the total impedance, or the double-layer capacitance, there was linear cor- relation between the detection time（DT） and the logl0 initial bacterial counts. Analyzed the examination error by the formula A=lg（Cc/Cspc）=Ig（Co）-Ig（Csec）, obtaining the conductance, the total impedance be more suitable than the doublelayer capacitance. Finally, compared the change tendency of FPR, FNR along with the DTTa, obtaining the suitable valUe of DTru can be 440 rain （the conductance and the total impedance as parameter）, 410 rain （the double-layer capacitanee as parameter）.

关 键 词：牛奶 阻抗 菌落总数 

分 类 号：TS252.7[轻工技术与工程—农产品加工及贮藏工程]