肖 贤，唐 林，陈 玲，雷 慧

（四川威尔检测技术股份有限公司，成都610041）

摘要：该文建立了菌落总数常规平板计数法的测量不确定度分析方法。鸡精样品按照GB 4789.2—2022《食品安全国家标准食品微生物学检验菌落总数测定》中的平板计数法测定菌落总数，依据RB/T 228—2023《食品微生物定量检测的测量不确定度评估指南》，系统分析了技术不确定度（u_tech）、基质不确定度（u_matrix）、泊松不确定度（u_Poisson）分量。通过分析10 批次市售鸡精的实验数据，得出技术不确定度为0.163 log₁₀ CFU/g，基质不确定度为0.062 4 log₁₀ CFU/g，泊松不确定度为0.163 log₁₀ CFU/g。合成标准不确定度与扩展不确定度分别为0.239 log₁₀ CFU/g和0.478log₁₀ CFU/g（k＝2）。该文为固体基质样品的微生物检测提供了多因素不确定度评估模型，对优化实验室质量控制流程及提升检测结果的可信度具有实际指导意义。

关键词：菌落总数；基质不确定度；泊松不确定度；扩展不确定度

中图分类号：TS264.23 文献标识码：A 文章编号：1674-506X（2025）05-0126-0005

Uncertainty Assessment of Total Bacterial Count Measurement in Chicken Essence

XIAO Xian，TANG Lin，CHEN Ling，LEI Hui

（Sichuan Will Test Technology Co.，Ltd.，Chengdu 610041，China）

Abstract: This study established an uncertainty measurement analysis method for plate counting method of total bacterial count. The total bacterial count of chicken essence samples was determined using the plate counting method in GB 4789.2—2022“National Food Safety Standard-Microbiological Examination of Food-Determination of Total Bacterial Count”. According to RB/T 228—2023“Guidelines for Evaluation of Measurement Uncertainty in Quantitative Detection of Food Microorganisms”，the technical uncertainty （u_tech），matrix uncertainty （u_matrix），and Poisson uncertainty （u_Poisson） components were systematically analyzed. By analyzing the experimental data of 10 batches of commercially available chicken essence，the technical uncertainty was found to be 0.163log₁₀ CFU/g，the matrix uncertainty was 0.062 4 log₁₀ CFU/g，and the Poisson uncertainty was 0.163 log₁₀ CFU/g. The combined standard uncertainty and expanded uncertainty are 0.239 log₁₀ CFU/g and 0.478 log₁₀ CFU/g，respectively （k＝2）.This article provides a multi factor uncertainty evaluation model for microbial detection of solid matrix samples，which has practical guidance significance for optimizing laboratory quality control processes and improving the credibility of detection results.

Keywords: total bacterial count；matrix uncertainty；Poisson uncertainty；expanded uncertainty

doi: 10.3969/j.issn.1674-506X.2025.05-016