Migration of novel offset printing inks from cardboard packaging into food

We report the migration potential of newly patented low-migration offset printing inks from cardboard food packaging and estimate the potential risk of their migration into food. The complete printing formulation was available and, due to the fact that the solvent compounds in these inks differ from those used in conventional printing inks, the investigation focused on these solvents. Instead of containing mineral and vegetable oils, the low-migration printing inks are based on a novel fatty acid ester. The migration of this alternative solvent was investigated according to DIN EN 14338 in Tenax simulant and in different types of food. For specific detection of the fatty acid ester, LC-MS/MS (APCI) was chosen due to its higher sensitivity and selectivity than GC/MS. Printed packaging materials from three different commercially available food products (meat, chocolate and sweets) were tested. Migration of the fatty acid ester from the packaging into simulants was analysed. For food samples, a clean-up method based on solid-phase extraction was developed and migration of the fatty acid ester into meat, chocolate and sweets was also demonstrated. Levels of contamination of these foods were between 5 and 80 microg fatty acid ester/kg, but levels in food were lower than those in simulants.