高效液相色谱法测定酱腌菜中脱氢乙酸含量的不确定度评定

Uncertainty evaluation for the determination of dehydroacetic acid in pickles by high performance liquid chromatography

目的评定高效液相色谱法(high performance liquid chromatography,HPLC)测定酱腌菜中脱氢乙酸含量的不确定度。方法根据GB 5009.121-2016《食品安全国家标准食品中脱氢乙酸的测定》中第二法液相色谱法,通过建立数学模型,识别测量过程中的各个不确定度来源,并对其进行分析和评定。结果当添加水平为50μg/mL时,酱腌菜中脱氢乙酸含量的测定结果为0.523g/kg,在95%的置信区间下,其扩展不确定度为0.098 g/kg(k=2)。结论对于高效液相色谱法测定酱腌菜中脱氢乙酸含量,其不确定度主要由配制标准溶液与拟合标准曲线构成。

Objective To evaluate the uncertainty for determination of dehydroacetic acid in pickles by high performance liquid chromatography(HPLC).Methods According to GB 5009.121-2016 National food safety standard-Determination of dehydroacetic acid in food,the second method of liquid chromatography,through the establishment of mathematical model,the sources of uncertainty in the measurement process were identified,analyzed and evaluated.Results When the addition level was 50μg/mL,the determination result of dehydroacetic acid in pickle was 0.523 g/kg,and the expanded uncertainty was 0.098 g/kg(k=2)at 95%confidence interval.Conclusion For the determination of dehydroacetic acid in pickles by HPLC,the uncertainty is mainly composed of standard solution and fitting standard curve.