A new study published online on November 12, 2014 in the peer-reviewed journal Dyes and Pigments investigates migration of printing inks from food contact materials (FCMs) (Aznar et al., 2014). Aznar and colleagues studied ink migration from different multilayer materials to two food simulants (ethanol 95% and Tenax®) and how it was affected by the addition of lacquers onto the material. Overall, a total of 24 migrants coming from inks were found to migrate from two multilayer materials. Further, 17 migrants alone were found to migrate out of one of the materials, namely a multilayer of ink/polyethylene terephthalate/aluminum/polyethylene. The set-off phenomena i.e., the unintentional transfer of components of printing inks from the outer printed surface of FCMs onto the inner non-printed food-contact surface, was identified as a mechanism of migration. When an external lacquer was added to the same material, the number of migrants decreased markedly. Further, new migrants were formed in the reaction between ink and lacquer. The authors conclude that the application of external lacquer coating can reduce the set-off phenomenon and thus migration of ink components into food. However, they stress that the composition of the chosen lacquer material is crucial. Not only does the lacquer not behave as a total barrier, it can also potentially contribute to the migration of new substances.
Aznar, M. et al. (2014). “Set-off of non volatile compounds from printing inks in food packaging materials and the role of lacquers to avoid migration.” Dyes and Pigments (published online November 12, 2014).