食品微生物检测试剂盒评价方法建立与应用

Establishment and application of test kits for detection of bacteria in food

目的建立实用可行的食品微生物检测试剂盒的评价方法。方法本研究以ISO 16 140为理论基础、GB 4789.10-2010为参比方法 ,从检测特异性、灵敏度、耐变性/统计学分析等方面对3M公司Petrifilm大肠埃希氏菌检测试剂盒(PEC)进行了可替代性评价。结果 PEC法对目标菌检测的特异性为84%,对非目标菌检测的特异性为100%;灵敏度检测中在25份低浓度添加样品里,PEC法的灵敏度有22份可以达到10 CFU/g,3份火腿样品的结果为阴性,国标法所有样品灵敏度均可达到10 CFU/g;耐变性评价中,PEC法在35℃/37℃、18 h/24 h耐变性条件的比较中检测结果差异均无统计学意义(P>0.05);应用2种方法对添加高、中、低3个水平的大肠埃希菌的五大类样品进行测试,线性方程为y=0.942 1x+0.328 4,相关系数为0.798 9,5类样品不同方法测试结果差异均无统计学意义(P>0.05);应用2种方法对30份自然样品进行检测,PEC法检测出4份阳性样品,国标法检测出6份阳性样品,2种方法阳性符合率为93.33%,差异无统计学意义(P>0.05)。结论以ISO 16140为理论基础可建立一套评价方法 ,此方法可系统的对微生物检测用试剂盒的可替代性进行评价。

Objective To establish a method for the detection of bacteria in food with test kit. Methods The study was based on ISO 16140. The GB4789. 10 - 2010 was used as the reference method. The petrifilm E. Coli/Coliform Count Plate（PEC） kit made by Minnesota Mining and Manufacturing Company was used in evaluations of specificity, sensitivity and stability of the kit. Results Fifty stains of target bacteria and 25 stains of discordant species bacteria were detected with PEC and the specificity was 84% for the detection of target bacteria and that for non-target bacteria was 100% , with the sensitivities of 10 colony-forming uint（ CFU）/g for low concentration isolates. Under different incubation conditions,the detection results of E. Coli at high, medium, and low concentration in 5 categories artificial samples of food showed no significant differences （ P 〉 0. 01 or P 〉 0. 05 ）. Conclusion With a series of ISO 16140 based evalua- tion method, the substitutability of test kit for detection of microorganisms in food could be evaluated.