顶空-气相色谱法测定动物源制品中三甲胺含量的测量不确定度评定

摘要

[目的]分析顶空-气相色谱法(HS-GC)测定动物源制品中三甲胺含量的测量不确定度来源并定量. [方法]建立(HS-GC)测定动物源制品中三甲胺含量的测量不确定度评定的数学模型,从测定程序各步骤评定不确定度的各项来源,对该方法所得结果的已识别来源的不确定度影响进行评价.[结果]该方法测定动物源制品中三甲胺含量的不确定度主要来源于三甲胺盐酸盐标准溶液及样品处理过程.当动物源制品中三甲胺含量为9.20 mg/kg时,其扩展不确定度为0.56 mg/kg(K=2,P=95%).[结论]该评定方法在实际工作中对提高三甲胺检测数据的可靠性与准确性具有一定指导意义.%[Objective]A mathematical model was established to assess the uncertainty in determination of trimethylamine in animal derived food by headspace gas chromatography.[Method]Various sources of uncertainty for measurement results during the analysis have been evaluated and the identified key factors were assessed.In this paper,the impacts of major source of measurement uncertainty were methanol standard solution and sample preparation.[Result]The uncertainty of trimethylamine in animal derived food determined by HS-GC originated mainly from trimethylamine standard liquid and sample treatment.When the trimethylamine content in animal derived food was 9.20 mg/kg,the expanded uncertainty of measurement results was 0.56 mg/kg(K=2,P=95%).[Conclusion]This uncertainty evaluation method shows certain guiding significance to improve the reliability and the accuracy of trimethylamine detection in practical work.