Bundesanstalt für Materialforschung und -prüfung (BAM), Richard-Willstätter-Straße 11, 12489, Berlin, Germany.
Anal Bioanal Chem. 2020 Jul;412(19):4659-4668. doi: 10.1007/s00216-020-02719-0. Epub 2020 Jun 2.
Since 1 January 2019 a maximum content of 0.6 mg kg cadmium (Cd) in cocoa powder sold to the final consumer or as an ingredient in sweetened cocoa powder sold to the final consumer (drinking chocolate) is set by the Commission Regulation (EU) No. 488/2014. Monitoring compliance with the specified limit value requires analytical measuring methods and reference materials for quality control. However, suitable certified reference materials intended for quality assurance and quality control purposes are still lacking. Therefore, three cocoa reference materials (ERM®-BD513, ERM®-514 and ERM®-515) were developed according to the requirements of ISO 17034 and the recommendations of ISO Guide 35. The whole process of reference material development, including material preparation, assessment of homogeneity and stability, characterisation and value assignment is presented. The assignment of the certified mass fractions was based upon an interlaboratory comparison study involving 19 expert laboratories for Cd and 12 laboratories for acrylamide. The certified mass fractions and expanded uncertainties (k = 2) of the reference materials were (0.181 ± 0.009) mg kg Cd (ERM®-BD513), (0.541 ± 0.024) mg kg Cd (ERM®-BD514) and (0.690 ± 0.029) mg kg Cd (ERM®-BD515). Acrylamide contents are given for information.
自 2019 年 1 月 1 日起，向最终消费者销售的可可粉或向最终消费者销售的加糖可可粉（饮用巧克力）中的镉（Cd）最大含量为 0.6mg/kg，由欧盟委员会法规 (EU) No. 488/2014 设定。监测对规定限值的遵守情况需要分析测量方法和质量控制参考材料。然而，仍然缺乏用于质量保证和质量控制目的的合适认证参考材料。因此，根据 ISO 17034 的要求和 ISO 指南 35 的建议，开发了三种可可参考材料（ERM®-BD513、ERM®-514 和 ERM®-515）。介绍了参考材料开发的整个过程，包括材料准备、均匀性和稳定性评估、特性描述和赋值。认证质量分数的赋值是基于涉及 19 个 Cd 专家实验室和 12 个丙烯酰胺实验室的实验室间比较研究。参考材料的认证质量分数和扩展不确定度（k = 2）为（0.181 ± 0.009）mg/kg Cd（ERM®-BD513）、（0.541 ± 0.024）mg/kg Cd（ERM®-BD514）和（0.690 ± 0.029）mg/kg Cd（ERM®-BD515）。提供丙烯酰胺含量供参考。
