顶空气相色谱法测定大豆油中苯残留量的不确定度评定

Uncertainty evaluation for determination of benzene residues in soybean oil by headspace gas chromatography

对顶空气相色谱法测定大豆油中苯残留量的不确定度进行评定。以JJF 1059.1-2012为依据,分析不确定度的来源,并确定各个不确定度分量以合成标准不确定度和扩展不确定度。结果表明,方法中引入的主要不确定度来源于标准曲线拟合,当大豆油中苯残留量为9.75 mg/kg,扩展不确定度为1.0 mg/kg,苯残留量表示为(9.75±1.0)mg/kg(k=2)。该评定方法可为顶空气相色谱法对大豆油中苯残留量的测定结果和方法的可靠性提供科学依据。

The uncertainty in determination of benzene residues in soybean oil by headspace gas chromatography(HS-GC)was evaluated.According to JJF 1059.1-2012,the uncertainty sources were analyzed.The combined standard uncertainty and expanded uncertainty were synthesized from their uncertainty components.The results showed that the main sources of uncertainty caused by standard curve ftting.When the benzene residues content in soybean oil was 9.75mg/kg,the expanded uncertainty was 1.0mg/kg and the benzene residues was expressed as(9.75±1.0)mg/kg(k=2).The method can provide a scientific basis for the measurement results and the reliability of the method of headspace gas chromatography for the determination of benzene residues in soybean oil.