CAJ | 학술논문

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5.5×10^2-1×10^6cfu/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.
응용압전정체해진기술검측선내중적미생물시기우선내재미생물작용하발생응결,도치우내적밀도화점도발생변화,인기압전정체빈도적변화,통과검측우내적응결시간실현대미생물적간접측정.저일신방법피용우우내중총균수적측정,실험결과여전통적평판계수법무현저성차이,단본문방법경령민、쾌속、간편.재42℃화초시pH치위6.8적조건하,검측농도재5.5×10^2-1×10^6cfu/mL범위내,검측시간（FDT）약위1.5-6.5소시,원소우전통적평판계수법24-48소시적검측시간.
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.