Multi-analyte methods for the detection of photoinitiators and amine synergists in food contact materials and foodstuffs – Part II: UHPLC-MS/MS analysis of materials and dry foods

Abstract

The aim of this investigation was to develop a multi-analyte method for the analysis of a total of 53 photoinitiators and amine synergists in food contact materials and foodstuffs. As for many of these compounds a maximum LOD of 10 µg kg⁻¹ food applies, a sensitive and selective detection method is needed to control at these limits. Here an UHPLC-MS/MS was chosen to achieve this object. In the end 49 compounds could be integrated into one analytical method. This is nearly twice as many compared with other by now available methods. Only 11.5 min are needed for the analysis of one sample, allowing a high sample throughput. The LODs, which were determined in acetonitrile in the absence of matrix interferences, are sufficient to control at the legally acceptable limits, except for five photoinitiators. The developed method was tested for the analysis of food contact materials and foodstuffs. In the latter case a muesli matrix was spiked at four different concentration levels to determine the recovery rates. Extractions were performed in each case with acetonitrile. For 87% of the photoinitiators and amine synergists recoveries from the muesli were in the range between 70% and 120%. Thus, a comprehensive detection method for the analysis of food contact materials and foodstuffs for these potential migrating substances is now available, allowing the safe identification and control of migration levels in foodstuffs for the majority of the tested compounds. In particular, this multi-analyte method is worthwhile for official control laboratories where normally no information about the composition of applied inks on the food contact materials is available and thus target analyses are not feasible.

Keywords:

• UV printing inks and varnishes
• food contact materials
• migration into food
• photoinitiators
• amine synergists
• UHPLC-MS/MS analysis

Acknowledgements

The authors would like to thank Mrs Maria Roth and Mr Werner Altkofer for the opportunity to perform this work at the CVUA Stuttgart, as well as Mrs Margot Heinz, CVUA Stuttgart, and Dr Thomas Glauner, Agilent Technologies Waldbronn, for skilful technical assistance; and the team from the commodities laboratory at the CVUA Stuttgart for valuable discussion.