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°C. Contrary to previous studies, coccobacilli and pleomorphic Gram-negative microorganisms (2-4 by 2-5 p.m) 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 HzS-producing fish spoilage bacteria, S. putrefaciens, as the maximum concentration of H2S-producing bacteria found in MAP fish products is wery 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.
Original language | English |
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Journal | International Journal of Food Microbiology |
Volume | 19 |
Pages (from-to) | 283-294 |
Number of pages | 12 |
ISSN | 0168-1605 |
Publication status | Published - 1993 |
Keywords
- Large gram-negative bacteria
- Photobacterium phosphoreum
- Shewanella putrefaciens
- Modified atmosphere
- Drip loss
- Fish spoilage