高效液相色谱法测定酱菜中脱氢乙酸含量的不确定度评定

Evaluation of Uncertainty for Determination of Dehydroacetic Acid Content in Pickles by High Performance Liquid Chromatography

采用高效液相色谱法测定酱菜中脱氢乙酸的含量,建立数学模型,分析不确定度来源,并对测定结果的不确定度进行了计算和评定,得出样品中脱氢乙酸的含量为0.122 g/kg,其扩展不确定度为0.003 g/kg,k=2。评定结果表明:对检测结果不确定度影响最大的是由标准曲线拟合求得的浓度,其次是测定的重复性。因此,在实验过程中操作人员应严格按照操作规程,检查分析影响因素,减小这些不确定度分量,从而提高测量结果的准确性。

The determination of dehydroacetic acid in pickles by high performance liquid chromatography is carried out.The mathematical model is established to analyze the source of uncertainty.The uncertainty of the determination results is calculated and evaluated.The content of dehydroacetic acid in the sample is 0.122 g/kg,the expanded uncertainty is 0.003 g/kg,k=2.The results show that the concentration obtained by standard curve fitting has the greatest influence on the uncertainty of test results,followed by the testing repeatability.Therefore,in the process of experiment,operators should strictly follow the operating procedures,check and analyze the influencing factors,reduce these uncertainty components,so as to improve the accuracy of determination results.