Packaging contact materials

The role of the business operators food industry and packaging/contact material industry... 

Both thermosets and thermoplastics are used as food-contact materials, though thermoplastics predominate in this appfication. Examples of the former are phenol- and urea-formaldehyde, while probably the best known example of the latter is low-density poly(ethylene). Other linear polymers are used include high-density poly(ethylene), poly(propylene), and PVC, all of which find quite extensive use. Polymers for food packaging may be in the form of films and other flexible items, or in the form of rigid containers, such as clear drinks bottles or opaque cartons for dairy products. 

Physico-chemical instrumental analysis nowadays has greatly suppressed such chemical handwork. An internet website disseminates methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). 

The enforcement in Denmark of EU Directives on food packaging materials is discussed. Enforcement activities considered include studies of total migration from food contact materials, migration from kitchen-and tableware made of melamine plastics and migration of di(2-ethylhexyl)adipate from plasticised PVC films. Activities which need to be undertaken to increase the effectiveness of enforcement activities in the field of migration are described, including development of selfinspection programmes in industry, European network of enforcement, more rapid analysis and provision of information to the consumer. 2 refs. 

The assurance of safety of packaging material encompasses all components, both those added to foods intentionally and those ending up in the food from the food-contact material or processing equipment. 

Additives that can be added indirectly to food through contact of the food with packaging materials, processing equipment, or other food-contact materials (see 21 CFR 174-178)... 

A change in the container closure system of unit dose packaging (e.g., blister packs) for nonsterile solid dosage fonn products, as long as the new package provides the same or better protective properties and any new primary packaging component materials have been used in and been in contact with CDER-approved products of the same type (e.g., solid oral dosage form, rectal suppository). 

Paper and board packaging is used mainly for secondary and tertiary packaging (e.g., labels, leaflets, cartons, and cases). Various dressings, pouches, and medical devices have paper as a contact material. 

Research on chemical migration from other types or components of packaging material - e.g. glass, wood, cork, coatings, adhesives - has been carried out sporadically. There is now a concerted UK programme to study chemical migration from these so that problems can be identified and dealt with in a consistent way (Working Party on Chemical Contaminants from Food Contact Materials and Articles, 1999). 

Food contact materials in general can be classified into ten main categories. As even a cursory glance around any supermarket will confirm the first four categories in this list dominate the packaging of our food in the developed world. 

Styrene monomer concentration in foods packaged in 31 different PS-containing food packages and contact materials averaged 224 mg/kg with two products having concentrations between 800 and 1500 mg/kg, well above the sensory threshold limits (Baner, 2000). Strict specifications for styrene monomers as well as for residual solvents, toluene, and odor and taint transfer for supplier materials should be set (Huber et al., 2002). 

Aurela, B., and Soderhjelm, L. (2007). Food packaging inks and varnishes and chemical migration into food. Ch. 13. In "Chemical Migration and Food Contact Materials" (K. A. Barnes, C. R. Sinclair, and D. H. Watson, eds.), pp. 302-319. Woodhead, Cambridge, England. 

In view of the necessity for getting waste disposal under control coupled with the limited fossil raw material resources, biodegradable polymer and in particular polymers from renewable resources will gain importance in the future. In the most sensitive application area, food contact materials and articles, it is possible initially to use these materials in very limited amounts. The easy decomposition of these packaging materials is in opposition with the inertness needed to protect packaged food. These polymers are particularly sensitive to moisture. By finishing operations such as surface treatments, one could improve the inertness of these polymers. However, the degradability would be diminished by such processes. 

Laoubi S. Feigenbaum A and Vergnaud J M, 1995, Safety of Recycled Plastics for Food Contact Materials Testing to Define a Functional Barrier. Packaging Technology and Science 8,17-27. 

Ethyl acetate, one of the most common presently used solvents for printing food contact materials, could cause many sensory problems with its very low odor threshold of 10 mg/kg. Assuming a complete transfer of ethyl acetate from the packaging into the product, it is calculated that the threshold level in Table 13-6 is reached with a package surface area to product mass of > 1 m2/kg based on a content in the material of 10 mg ethylacetate per m2. This could only be the case for small packages or for foods with a low fill weight (e.g. potato chips). With the present state-of-the-art technology the residual amounts of ethylacetate are usually under 10 mg/m2 and can be monitored analytically without difficulty. 

Intelligent food contact materials are those that provide the consumer with information on the status of the packaged food or the atmosphere in the... 

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