CAJ | 학술논문

目的：建立食品菌落总数测定的通用数学模型和测量不确定度的评定方法。方法按照加权平均的算法对菌落总数计算公式进行推导,建立了菌落总数计数方法的通用数学模型。以某橙汁饮料菌落总数的测定过程为例,从三个方面分析并量化了各不确定度的分量,分别为：不同稀释度平板上菌落数的分布(以同一稀释度上两个平板计数结果的相对相差表示),样品移取和稀释过程(以各量具的容量允差及稀释过程对稀释倍数贡献的相对不确定度表示),数字修约(以修约间隔引入的粗大误差表示)。按照均方根法则,将各计数平板的测量不确定度进行加和,即为总测量不确定度。结果本例中该橙汁饮料菌落总数的扩展不确定度 U=0.2×104 CFU/mL, k=2。结论建立了简便准确的食品菌落数测量不确定度的评定方法。
목적：건립식품균락총수측정적통용수학모형화측량불학정도적평정방법。방법안조가권평균적산법대균락총수계산공식진행추도,건립료균락총수계수방법적통용수학모형。이모등즙음료균락총수적측정과정위례,종삼개방면분석병양화료각불학정도적분량,분별위：불동희석도평판상균락수적분포(이동일희석도상량개평판계수결과적상대상차표시),양품이취화희석과정(이각량구적용량윤차급희석과정대희석배수공헌적상대불학정도표시),수자수약(이수약간격인입적조대오차표시)。안조균방근법칙,장각계수평판적측량불학정도진행가화,즉위총측량불학정도。결과본례중해등즙음료균락총수적확전불학정도 U=0.2×104 CFU/mL, k=2。결론건립료간편준학적식품균락수측량불학정도적평정방법。
Objective To establish the general mathematical model and the procedure of measurement uncertainty for the determination of the Aerobic Plate Count (APC) on food. Methods According to the weighted average method, the formula of the APC was derived, and a general mathematical model was established. To take the measurement process of an orange juice drink APC as an example, three uncertainty components were evaluated and expressed, including the distribution of colony forming units (CFUs) on selected plates at different dilutions (equal to the relative difference of CFUs at the same dilution plates), the sampling and diluting process (equal to the relative uncertainty of dilution factor from capacity allowable errors and dilution process cumulative errors), rounding off numerical values (equal to gross error of rounding interval). According to the root-mean-square principle, measurement uncertainty components of each plate were added to calculate the total measurement uncertainty. Results Expanded uncertainty for the APC is 0.2×104 CFU/mL, k=2. Conclusion A simple and accurate method for evaluating measurement uncertainty for the APC of food is established.