Microbiological Changes in Prepacked Cod Fillets in Relation to the Oxygen Permeability of the Film

The deterioration of prepacked cod fillets in relation to the oxygen permeability of the polyethylene film was studied bacteriologically and chemically. Spoilage at 0° is not related directly to oxygen permeability (OP). The deterioration curve at higher storage temperatures (3 and 6°) is of the same form as the curve at 0°. Moreover, from the curve it can be deduced that a film with c. 3600 ml/m²/24 h OP gives the best results. A maximum spoilage is observed with an OP c. 1800 ml/m²/24 h. Identical results were obtained with other films. The formation of formalin bound volatile nitrogen compounds is inhibited in prepacked fish whereas the trimethylamine content increases.