The effectiveness of hexamethylenetetramine-incorporated plastic for the active packaging of foods

The feasibility of LDPE films containing 0.2 or 0.5% (w/w) hexamethylenetet ramine (HMT) as antimicrobial packaging I material to inhibit microbial gro wth an the surface of foods was investigated. As HMT is allowed in Europe t o be used as a preservative under certain conditions, and as it is mentione d on the list of additives notified to the European Commission as substance s which may be used in plastics intended in contact with food products, thi s compound offers good opportunities for the manufacturing of an antimicrob ial packaging material. In a first experiment, fresh orange juice was vacuu m packaged in LDPE films containing 0, 0.2 and 0.5% (w/w) HMT and stored at 6 degrees C for 39 days. Every day and later every 3 days, packages of ora nge juice were analysed for yeasts and lactic acid bacteria. The shelf-life of orange juice, could not be prolonged significantly by packaging into a 0.2% or 0.5% (w/w) HMT-containing film. In a second experiment, however, pa ckaging of cooked ham in a 0.5% (w/w) containing LDPE film, significantly a ffected shelf-life. After 20 days a significant reduction of total aerobic count and lactic acid bacteria was observed. In an additional migration tes t, it became clear that the level of HMT released into orange juice was clo se to the specific migration limit of 15 mg CH2O/kg imposed by the EC. Copy right (C) 2000 John Wiley & Sons, Ltd.