乳粉中维生素B1和B2含量测定的能力验证分析

目的为加强我国检测机构对乳粉市场的监管,中国食品药品检定研究院(National Institute for Food and Drug Control,NIFDC)组织实施了乳粉中维生素B_1和B_2的含量测定的能力验证。方法制备了分割水平对的样品,采用单因素方差分析和t检验对样品均匀性和稳定性进行分析。对能力验证结果进行稳健统计分析,通过Z比分数评价实验室检测能力。结果样品通过均匀性和稳定性检验要求,满足能力验证计划要求。维生素B_1项目中,参加20个实验室验证,满意结果数为14,满意率为70.0%;维生素B_2项目中,参加22个实验室验证,满意结果数为15,满意率为77.2%;2项检测结果均满意的实验室有12个,满意率为60%。结论绝大多数实验室对乳粉中维生素B_1和B_2的测定处于良好水平,但未达到优良水平,仍需对检测方法进行统一认识,减少系统误差,加强各实验室内部的质量控制。

Analysis of proficiency testing on the quantification of vitamin B1 and B2 in milk powder

Objective To strengthen the supervision of milk powder market in Chinese inspection institutions, National Institute of Food and Drug Control (NIFDC) organized the proficiency test on the quantitation of vitamin B1 and vitamin B2 in milk powder. Methods Samples with split horizontal pair were prepared, and the uniformity and stability of samples were analyzed by one-way ANOVA and t test, respectively. Robust statistical analysis of proficiency testing results were conducted to evaluate laboratory testing ability through Z score. Results The homogeneity and stability of the sample met the requirements of proficiency testing. A total of 20 laboratories participated in the determination of vitamin B1, among which 14 laboratories had satisfactory results, accounting for 70.0%; 22 laboratories participated in the determination of vitamin B2, among which 15 laboratories had satisfactory results, accounting for 77.2%; and 12 laboratories had both satisfactory detection results, with the satisfaction rate of 60%. Conclusion For most of participated laboratories, the determination level of vitamin B1 and B2 in milk powder is good, but cannot be excellent yet. It is still necessary to make a unified understanding of detection methods, reduce system errors, and strengthen quality control in laboratories.