Abstract: Chromium is an important analytical item in food quality and safety monitoring. Two common methods to detect chromium in food: graphite furnace atomic absorption spectrometry (GF-AAS) and inductively coupled plasma mass spectrometry (ICP-MS) are specified in the National Food Safety Standard Determination of Chromium in Foods (GB 5009.123-2023). This study systematically evaluated the stability, bias, linearity, repeatability, and reproducibility of the two methods using Minitab statistical tools by control chart, independent sample, t test and analysis of variance (ANOVA) methods. The results showed that no outliers were found in the range or mean plots for each method, with within-group errors under statistical control and good stability; the results of gauge linearity and bias analysis showed no significant bias or significant linear error; the gauge repeatability and reproducibility (R&R) analysis showed good repeatability and reproducibility. Two-way ANOVA showed that the sample was the only factor that significantly affected the measurement error. Research variation analysis showed that the measurement system error was acceptable. ICP-MS and GF-AAS can effectively ensure the reliability and repeatability of the detected data of chromium content in milk powder. The findings of this study can not only provide a scientific basis for laboratory analysis and control of measurement system errors, but also provide a reference for the evaluation of measurement systems for the determination of other heavy metals in dairy products and other foods.

Key words: inductively coupled plasma mass spectrometry; graphite furnace atomic absorption spectrometry; milk powder; chromium; Minitab; measurement system

摘要： 铬元素是食品质量安全重点监测项目, GB 5009.123—2023《食品安全国家标准 食品中铬的测定》中规定了食品中铬的2 种常用检验方法：石墨炉原子吸收光谱（graphite furnace atomic absorption spectrometry, GF-AAS）法和电感耦合等离子体质谱（inductively coupled plasma mass spectrometry, ICP-MS）法。使用Minitab统计分析工具, 运用控制图法、独立样件法、t检验法及方差分析法对上述2 种常用检验方法测量系统的稳定性、偏倚、线性、重复性与再现性进行分析。结果表明：2 种检测方法测量系统极差图和均值图均无异常点, 组内误差处于统计受控状态, 稳定性良好；量具线性和偏倚分析结果均不存在显著偏倚和显著线性误差；量具R&R报告分析结果表明, ICP-MS法和GF-AAS法测量系统重复性和再现性良好；双因子方差分析表明, 样品是唯一显著影响测量误差的因子；研究变异分析表明, 测量系统误差可以接受。ICP-MS法和GF-AAS法不仅能有效保障乳粉中铬元素含量检测数据的可靠性和可重复性, 为实验室进行测量系统的误差分析与控制提供科学依据, 同时也为乳制品中其他重金属检测及其他食品中重金属检测的测量系统评价提供一定参考。

关键词: 电感耦合等离子体质谱；石墨炉原子吸收光谱；乳粉；铬；Minitab；测量系统