Abstract: To evaluate the measurement uncertainty in the microbiological determination of the vitamin B6 content in milk powder, we estimated various uncertainty sources according to the National food safety standard for the determination of vitamin B6 in foods (GB 5009.154-2023) and the Evaluation and expression of uncertainty in measurement (JJF 1059.1-2012), and calculated combined standard and extended uncertainties. The results showed that the content of vitamin B6 in milk powder was (9.34 ± 1.23) mg/kg (k = 2, p = 95%). Through uncertainty component analysis, it was found that measurement repeatability and the preparation of standard solution had a significant impact on the determination of the vitamin B6 content in milk powder.

Key words: microbiological method; milk powder; vitamin B6; uncertainty

摘要： 为评定微生物法测定乳粉中VB6含量的不确定度，依据GB 5009.154—2023《食品安全国家标准 食品中维生素B6的测定》及JJF 1059.1—2012《测量不确定度评定与表示》对微生物法测定乳粉中VB6含量过程中产生的各不确定度进行分析，计算合成标准不确定度、扩展不确定度。结果显示，乳粉中VB6的含量为（9.34±1.23）mg/kg（取包含因子k＝2，包含概率p＝95%）。通过不确定度分量分析可知，测量重复性和标准溶液的制备对乳粉中VB6含量测定影响较大。

关键词: 微生物法；乳粉；VB6；不确定度