A Study into the Suitability of Several Food Simulating Matrices for Migration Testing of Michler's Ketone and Related Aromatic Amines from Food Packaging Cardboard Materials

The migration behaviour of Michler's ketone (MK) from experimental polyethylene-coated and non-coated cardboard samples into various food simulating matrices has been investigated and evaluated. As aqueous simulants, 3 % acetic acid and 10 % ethanol and as an alternative fat simulant 95 % ethanol were selected. In addition, the feasibility of Tenax (modified polyphenylene oxide) as alternative or substitute fatty food simulant matrix has also been studied. Although the concentration values of MK in the cardboard samples were below 0.2 µg/g in all cases, significant migration of MK into 95 % ethanol and on Tenax was determined. The latter fat substitute matrix proved to be a very convenient alternative to the regular fat test with olive oil. Besides, as aminobenzophenone derivatives are highly photoreactive compounds and due to the absence of data until present about their reactivity under standard migration test conditions, stability studies have been carried out including also other aromatic amines related to MK. While all the studied compounds were quite stable in all of the non-acidic simulants, noticeable degradation of MK was observed in aqueous acetic acid, which can be a serious limitation for the validity of this test. Although the use of MK as raw material in printing inks manufacturing for food packaging is not recommended nowadays by the printing inks industry and its placement on an exclusion list, the presence of MK as potential migrant in food packaging materials may occure due to its possible formation by chemical or photodegradation of several violet dyes or pigments