基于压电传感技术的鲜奶总菌数快速检测方法研究  

Rapid Detection of Total Bacteria Content in Milk Based on Piezoelectric Technique

作　　者：汪学英[1] 孙明伟[1] 顾锋[1] 吴金男[1] 尹凡[1] 

机构地区：[1]常熟理工学院化学与材料工程学院,江苏常熟215500

出　　处：《常熟理工学院学报》2011年第10期15-18,70,共5页Journal of Changshu Institute of Technology

摘　　要：应用压电晶体谐振技术检测鲜奶中的微生物是基于鲜奶在微生物作用下发生凝结,导致牛奶的密度和粘度发生变化,引起压电晶体频度的变化,通过检测牛奶的凝结时间实现对微生物的间接测定.这一新方法被用于牛奶中总菌数的测定,实验结果与传统的平板计数法无显著性差异,但本文方法更灵敏、快速、简便.在42℃和初始pH值为6.8的条件下,检测浓度在5.5×102-1×106cfu/mL范围内,检测时间(FDT)约为1.5-6.5小时,远少于传统的平板计数法24-48小时的检测时间.A piezoelectric sensor was utilized to determine the number of bacteria based on the coagulation of milk in which microorganism had grown, and in the process of coagulation of milk the viscoelastic status changes and so the frequency shifts. The coagulation of gelatin was monitored and the number of bacteria was determined indirectly. This new method was applied to determine the total number of bacteria. The result indicated that there does not exist a significant difference compared with the traditional standard plate count method. However, it was more sensitive, rapider, and more convenient. At 42℃ and pH=6.8 , from the concentration of 5.5× 10 2 to 1×10 6 cfu/mL of bacteria, the time of detection was only about 6.5 to 1.5 h, which was much shorter than that of 24-48 h by the traditional standard plate count method.

关 键 词：压电传感器 细菌总数 牛奶 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置]