title: Spoilage and shelf-life of cod fillets packed in vacuum or modified atmospheres.
abstract: Microbial growth, sensory and chemical changes and composition of gas atmosphere were studied in vacuum packed (VP) and modified atmosphere packed (MAP) cod fillets stored at 0 degree C. Contrary to previous studies, coccobacilli and pleomorphic Gram-negative microorganisms (2-4 by 2-5 microns) and not Shewanella putrefaciens were found most likely to be the main spoilage organisms. These microorganisms, which may be Photobacterium phosphoreum, can explain the short shelf-life extension of VP and MAP fish products compared to meat products. It is suggested that they may inhibit the typical H2S-producing fish spoilage bacteria, S. putrefaciens, as the maximum concentration of H2S-producing bacteria found in MAP fish products is very low. Compared to VP, a shelf-life extension of 6-7 days was obtained with 48% CO2 in MAP. However, with pure CO2 the shelf life was only extended by 2-3 days. Poor texture and high drip loss indicated that the shelf life of these fillets was limited by chemical reactions and not only by microbial activity.
authors.affiliation: Technological Laboratory, Danish Ministry of Fisheries, Technical University, Lyngby.
authors.forename: P
authors.initials: P
authors.lastname: Dalgaard
authors.forename: L
authors.initials: L
authors.lastname: Gram
authors.forename: H H
authors.initials: HH
authors.lastname: Huss
mesh_terms: D000818:Animals; D002245:Carbon Dioxide / Q000494:pharmacology; D004123:Dimethylamines / Q000378:metabolism; D005399:Fishes / Q000382:microbiology*; D005511:Food Handling; D005516:Food Microbiology; D005519:Food Preservation; D006090:Gram-Negative Bacteria / Q000187:drug effects / Q000254:growth & development* / Q000302:isolation & purification; D019271:Hypoxanthine; D007042:Hypoxanthines / Q000378:metabolism; D008744:Methylamines / Q000378:metabolism; D016877:Oxidants / Q000378:metabolism; D014618:Vacuum
chemical_list: D004123:Dimethylamines; D007042:Hypoxanthines; D008744:Methylamines; D016877:Oxidants; D002245:Carbon Dioxide; D019271:Hypoxanthine; C034516:dimethylamine; C005855:trimethyloxamine; C023336:trimethylamine