Barriers Against the Migration from Recycled Paperboard into Food: Measuring Efficiency by Surrogate Components

摘要

Functional barriers might soon be required by certain countries to protect foods against contaminants from recycled paperboard used as primary packaging or transport boxes. Such a requirement presupposes a method for specifying and checking the efficiency of a barrier. The proposed method uses four surrogate compounds of similar boiling point covering a broad range of polarities: n-heptadecane, 4-methyl benzophe-none, dipropyl phthalate and triethyl citrate. They are applied to a donor paper that is attached to one side of the barrier (plastic film or lined paperboard). On the other side, a silicone paper absorbs the material broken through the barrier. Periodically, pieces of this silicone paper are extracted and analysed by gas chromatog-raphy and flame ionization detection. The performance of the method was tested on various barrier materials of modest efficiency using a mixture of 12 test substances, varying the molecular mass for a given substance type of which a member was finally selected. Large differences in selectivity were observed, i.e. properties of a given barrier for different types of components, but also for varied molecular mass/volatility vary widely.