料酒中总酸和氨基酸态氮测定的不确定度评定

Evaluation of Uncertainty in Determination of Total Acid and Amino Acid Nitroogenin Cooking

为确保测量结果的真实准确性,合理定量表征谷物酿造料酒中总酸和氨基酸态氮的含量,并对其进行不确定度评定。依据T/CBJ 8101—2019《谷物酿造料酒》测定谷物酿造料酒中总酸和氨基酸态氮含量,建立数学模型,并结合JJF 1059.1—2012《测量不确定度评定与表示》分析评定各个不确定度的来源。结果表明,取置信区间P=95%,包含因子k=2,可得扩展不确定度,得到的谷物酿造料酒中总酸(以乳酸计)结果为4.65±0.06 g/L,氨基酸态氮(以氮计)结果为0.65±0.01 g/L。该不确定度评定适用于酸度计法测定谷物酿造料酒中总酸和氨基酸态氮含量的过程分析,对把控测量结果的准确度具有指导意义,为其他食品不确定度评定的研究与应用提供有益参考,从而不断提高实验室的检验水平。

In order to ensure the accuracy of measurement results,the contents of total acid and amino acid nitrogen in grain-brewing cooking wine were quantitatively characterized,and their uncertainty was evaluated.The contents of total acid and amino acid nitrogen in grain-brewing cooking wine were determined according to T/CBJ 8101—2019 Grain-brewing Cooking Wine,mathematical models were established,and the sources of uncertainty were analyzed and evaluated according to JF 1059.1-2012 Evaluation and Expression of Measurement Uncertainty.The results showed that taking the confidence interval P-95%,including factor k-2,the extended uncertainty could be obtained.The total acid(lactic acid)in grain-brewing cooking wine was 4.65±0.06 g/L.Amino acid nitrogen(calculated by nitrogen)was 0.65±0.01 g/L.The uncertainty evaluation could be applied to the process analysis of the determination of total acid and amino acid nitrogen in grain-brewing rice wine by acidity meter,which had guiding significance for controlling the accuracy of measurement results,and provided useful reference for the research and application of uncertainty evaluation of other foods,thus improving the laboratory testing level.