Food safety and quality are two of the most important factors determining consumer acceptance of a product. Proof of authenticity, fraud detection, and the identification of residues and contaminants, e.g. heavy metals such as cadmium and lead, are therefore of general interest.
Since 1st January 2019, Commission Regulation (EU) No 488/2014 sets a maximum content of 0.6 mg kg-1 cadmium (Cd) in cocoa powder. In order to monitor the compliance with this limit, suitable and validated analytical methods and reference materials for quality control are required. BAM has therefore developed three cocoa reference materials (ERM®-BD513, ERM®-BD514 and ERM®-BD515) to remedy this deficiency. The whole process of reference material development including material preparation, evaluation of material homogeneity and stability, characterization, and value assignment is described in this publication.
At the core of the development of reference materials at BAM are the requirements imposed by ISO 17034 and the recommendations of ISO Guide 35. The assignment of the certified property values was done based on a certification interlaboratory comparison involving 19 specialised laboratories for Cd and 12 laboratories for acrylamide analysis and quantification. The certified Cd mass fractions of the three reference materials were distributed around the limit value of 0.6 mg kg-1 so that the user can make a safe decision whether their reals samples are within the limit or not. Due to the low stability of acrylamide in the cocoa powder, its content was given for information only and was not certified.
Development of certified reference materials for the determination of cadmium and acrylamide in cocoa
Sebastian Recknagel, Matthias Koch, Robert Köppen, Sabine Buttler, Sibylle Penk, Tatjana Mauch, Thomas Sommerfeld, Angelika Witt
published in Analytical Bioanalytical Chemistry, Vol. 412, pages 4659–4668, 2020.
BAM, Division Inorganic Reference Materials and Division Organic Trace and Food Analysis