SHELF-LIFE OF SLICED SMOKED, SALMON PACKA GED WITH DIFFERENT MODIFIEDATMOSPHERES - EXPERIMENTAL RESULTS

Modified atmosphere packaging (MAP) is used to extend the shelf-life o f highly perishable foods, like sliced cold-smoked salmon. The object of this study was to determine the preserving potential of smoked Atla ntic and silver salmon in three different modified atmospheres by moni toring the chemical, microbiological and sensory changes of the produc t in packages containing carbon dioxide, oxygen and nitrogen. The comp osition of the gas atmospheres used for storage was respectively: A) 7 0% CO2- 25% N2 -5% O2; B) 95% CO2 -5% O2; C) 60% CO2 -25% O2 -15% N2. The trays were held at +2/3-degrees-C and opened at various storage ti me (till 60 days in S. salar and 120 days in O. kisutch). Spoilage bac teria growth was markedly inhibited by the presence of CO2 and by lact obacilli growth in all treatment groups used throughout the study. Sen sory, chemical (TVBN, TMA-N and TBA) and microbial evaluations indicat ed that the product held in the A gas mixture was of better quality th an the others, at least till the end of storage in S. salar and till 1 00 days in O. kisutch. The samples stored in B mixture (without nitrog en) presented a higher proteolysis, while those in C mixture manifeste d a slight but perceptible sour odor after 15 days.