Sensory, chemical, and microbiological analyses were carried out on sardines during 18 d of storage in ice. Sensory results indicate that the sardines used in this experiment had a shelf life of 9 d. The pH and dimethylamine (DMA) were found to be useless in determining the degree of sardine deterioration, while trimethylamine (TMA) and total volatile bases (TVB) were accurate in predicting the spoilage process. Histamine production was slowed by refrigeration in ice (2–4°C). The amounts of histamine in flesh at the time of rejection (12th day of storage) were 11.7 and 16.2 mg/100 g of flesh, respectively, with the colorimetric method and the fluorimetric method. At the end of the experiment (highly spoiled sardines), the critical value of histamine (20 mg/100 g) was not reached. However, at the 12th d of storage, the count of all microflora studied was above the limit of 106 CFU/g of flesh.

Freshness of ice-stored sardine was assessed by two sensory methods, the quality index method (QIM) and the European Union freshness grading system, and by instrumental means using the method of aroma extract dilution analysis. Screening of sardine potent volatiles was carried out at three freshness stages. In the very fresh state, the plant-like fresh volatiles dominated the odor pattern, with the exception of methional. Overall odor changes in sardine throughout storage correlated with changes in the concentration of some potent volatiles: after 2 days of ice storage, (Z)-4-heptenal, (Z)-1,5-octadien-3-one, and methional imparted an overall "fishy" odor character to sardine, whereas at a lower sensory grade (B), the compounds (E)-2-nonenal and (E,Z)-2,6-nonadienal could be, in part, associated with the slightly rancid aroma top notes. Trimethylamine was detected as a highly volatile odorant using solid-phase microextraction (SPME) headspace analysis of refrigerator-stored sardine. Intensity and sensory characteristics of some SPME determined volatiles, for example, 3-methylnonane-2,4-dione, were closely related to overall odor changes. SPME headspace analysis may be useful in the characterization of off-flavors in fish.

Rotaviruses from environmental samples have been genotyped by a seminested reverse transcription PCR assay with serotype-specific primers derived from variable regions of gene 9, which produce different characteristic segment sizes for serotypes 1 to 4. The method enabled the detection and identification of type 1, 2, and 3 group A rotaviruses in sewage.

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A risk assessment of histamine was conducted for different categories of fishery products in the market. Risk estimates were assessed using the Risk Ranger tool. The estimated risks associated with the consumption of canned, semi-preserved and frozen fish are lower than those associated with fresh fish. According to the hypotheses of application or not of the histamine control measures, two risk levels were calculated for each product. The highest risk is associated to sardine with a score of 35 (equivalent to 39 patients per year). With the application of control measures, the score decreases to 20 (equivalent to one patient per year) with a reduction of 38 patients estimated per year. The risk ranking for frozen fish varies between zero (1 patient for 1000 years) and 11 (three patients for 1000 years). For semi-preserved fish, it ranges from zero to 21. For canned fish, the risk ranking varies between 12 (five patients for 1000 years) and 21 (15 patients for 100 years). As a result, most Moroccan seafood products are classified as “low risk”. However, it is recommended that risk managers maintain the adopted measures, strengthen interventions upstream in the food chain and that professionals maintain the HACCP (Hazard Analysis Critical Control Point) system effectively.