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

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