大黄鱼中大肠菌群测量不确定度评定

Evaluation of Uncertainty in Measurement of Coliform Bacteria inPseudosciaena Crocea

建立大黄鱼中大肠菌群不确定度评定方法。依据GB 4789.3—2016第二法对同1份大黄鱼样品进行18次重复检测;依据JJF 1059.1—2012等对检测过程样品处理、样品稀释、加样体积、重复检测等操作产生的不确定度分量进行分析计算。结果表明,大黄鱼样品中的大肠菌群扩展不确定度为u=0.050(取置信概率p=95%,k=2.11),微生物分布不均匀使得检测过程中的不确定度分量主要来自于样品重复测量,即A类测量不确定度分量大,B类不确定度分量小。

This study established the uncertainty evaluation method of coliform group in pseudosciaena crocea.According to the second method of GB 4789.3—2016,the same large yellow croaker sample was detected 18 times according to JJF 1059.1—2012,the uncertainty components of sample processing,sample dilution,sample adding volume and repeated detection were analyzed and calculated.The results showed that the uncertainty of coliform expansion in pseudosciaena crocea was u=0.050(p=95%,k=2.11),because of the uneven distribution of microorganisms,the uncertainty components in the detection process mainly come from the repeated measurement of samples,i.e.,the uncertainty components of Class A are large,and the uncertainty components of Class B are small.