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The self-life, quality and safety of refrigerated sardine fillets (Sardina pilchardus) were determined at 3• C in atmospheric air, vacuum and modified atmosphere (50% CO 2 /50% N 2 ) packaging conditions. Microbiological, physico-chemical and sensory parameters were utilised as quality indicators. The microbial flora of sardine comprised -according to order of occurrence -Shewanella putrefaciens, pseudomonads, Brochothrix thermosphacta, lactic acid bacteria and, finally, Enterobacteriaceae. Bacteria grew most quickly in sardines stored in air, followed by those in vacuum packaging, and the lowest counts were found in modified atmosphere packaging. The concentrations of moisture, ash, protein, fat and polyunsaturated fatty acids were not affected during the storage period compared to the pH values and the concentrations of lactate and ammonia that showed significant differences. INTRODUCTIONSeafood is highly perishable, generally spoils faster than other muscle foods and is also more susceptible to post-mortem texture deterioration than other meats.

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The fate of three pathogens Salmonella Enteritidis, Listeria monocytogenes and Escherichia coli O157:H7 that were inoculated in fish roe salad and aubergine salad with or without preservatives after being adapted in acid environment or not, was determined. The salads were stored at 10°C and the pathogens population was counted at regular intervals. Parameters (lag time, death rates calculated with Baranyi equation) were used to compare the behaviour of the pathogens. In the absence of preservatives the pathogens survived during the 15 days of storage. A 1 log reduction was observed for Listeria and 2 logs reduction for Salmonella and E. coli in both salads. In most cases, acid adaptation decreased the death rate even in the presence of preservatives. The addition of sorbic and benzoic acid in the salads increased the death rate of the pathogens during storage significantly and they were not detected at 7-10 days for Salmonella, 8-12 days for Listeria and 5 days for E. coli. It is concluded that a well-studied combination of hurdles is appropriate to ensure safety of home-made traditional salads free of preservatives.

The ripening period for salted sardines ranges from 4 to 6 months, depending on the season. Sometimes producing industries need to distribute the product earlier owing to market needs, and when this happens the product's safety needs to be assured. The purpose of this work was to study the survival of Staphylococcus aureus and Salmonella Enteritidis on salted sardines during a ripening period of 115 days. Salted sardines were inoculated with pure cultures of S. aureus and Salmonella Enteritidis (10(5) CFU/g of fish on day 0). After 5 days of ripening, the water activity value for the sardines decreased from 0.93 to 0.69. The survival of both pathogens and that of total viable cells were evaluated during the ripening process. Total viable counts decreased by 2 log units over the 115-day ripening period. Salmonella Enteritidis and S. aureus survived for 60 and 90 days, respectively. Therefore, the use of a 90-day ripening period could be effective in assuring the safety of the final product.

Summary Microbiological changes were studied in minced beef and minced dark, firm, dry (DFD) pork stored under different atmospheres (100% in carbon dioxide, nitrogen or air) at 3°C. The storage life (time for 100‐fold increase in TVC) of samples flushed with carbon dioxide was increased by c. 3–4 days. Pseudomonads were the dominant organisms in samples stored in air, and lactic acid bacteria and Brochothrix thermosphacta in those stored under carbon dioxide. There was an alkaline drift in all samples, but at different rates (air > nitrogen > carbon dioxide). The rate of glucose assimilation in normal and DFD beef was slower in the samples stored under carbon dioxide than those under nitrogen or air. Lactate, gluconate, acetic acid, ethanol and diacetyl occurred in normal and DFD beef regardless of the storage atmospheres.

Chemical, microbial and sensory quality aspects of the marinated ascidia Microcosmus sabatieri Roule, 1885, were examined over a 150-day period at 6°C, under vacuum and air (control) packaging conditions using three different formulations (with 12% sodium chloride and 3%, 5% or 7% acetic acid). Significant differences were found between chemical and sensory analysis of three different marinated groups (P > 0.05) during the storage period. There were also significant differences in pseudomonads, lactic acid bacteria and yeast and moulds of the marinated groups by which lower bacterial counts were determined. N-3 polyunsaturated fatty acids concentrations decreased significantly (P < 0.05), while total viable counts, ammonia and total saturated fatty acid concentrations increased significantly (P > 0.05) in all three groups during storage. The differences in fatty acid and ammonia concentrations were found to be useful as indexes of freshness and decomposition of marinated M. sabatieri in storage. Shelf life of M. sabatieri marinades was found to be 5 and 4 months under vacuum and air (control) packaging conditions respectively, at 6°C.