Gilthead sea bream (Sparus aurata) were stored in melting ice (0 °C) for a period of 24 days from the time of harvest with sensory assessments of the whole raw fish and of the cooked fish flesh conducted at regular intervals. The ungutted fish was given an EC freshness grade E for up to 3 days, grade A for a further 7 days, and grade B for 4 more days after which it was graded as C (unfit). The sensory score for flavour of the cooked fillets decreased linearly with period of storage: fresh characteristic flavours were present for 2–4 days, decreasing to a relatively bland flavour after 10–12 days. Off flavours were evident by 13–15 days storage and by 18–19 days the flesh was unpalatable. With the possible exception of hypoxanthine, none of the chemicals investigated was particularly useful as an indicator of change. Changes in pH, trimethylamine and total volatile bases during the first half of the edible storage life were insignificant. Deterioration of flesh lipids, assessed by free fatty acid content and thiobarbituric acid value, appeared to present no serious problem during shelf‐life. Proximate composition and sensory attributes, appropriate for routine inspection of gilthead sea bream were also determined.

Farm raised European sea bass (Dicentrarchus labrax) were stored in melting ice for a period up to 22 days from the time of harvest, and sensory, chemical, and microbiological assessments were made at intervals. The storage life of the ungutted fish, determined by sensory evaluation of the cooked flesh, was 19 days. Of the chemical tests, only k1 value provided a useful means of monitoring early storage change. Trimethylamine, total volatile bases and pH showed practically no change during the first half of the edible storage life of the fish. Changes in free fatty acid (FFA) content and thiobarbituric acid (TBA) value could not be used to determine loss of acceptability or end of storage life. Sulphide producing bacteria constituted a very low proportion of the total aerobic flora, suggesting that the common sulphide producer Shewanella putrefaciens was not a major spoiler of sea bass in this trial.

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The objective of this work is the comparative study of different osmotic treatments at 37 °C on the quality and shelf life of chilled sea bass fillets. Fish fillets were treated using osmotic solutions consisting of oligofructose (40%–50%–60%) and 5% NaCl with (BP/OT) and without (OT) former antioxidant enrichment by using Rosa damascena distillation by-products. Water activity decreased to approximately 0.95 after 330 minutes of osmotic treatment. Untreated and osmotically treated fish fillets (BP/OT) and (OT) were subsequently stored at 5 °C and their quality was evaluated based on microbial growth and lipid oxidation. Osmotic treatment extended significantly the shelf life of fish in terms of microbial growth; however, it also accelerated its lipid oxidation. The impregnation of Rosa damascena phenolics not only counterbalanced this negative effect, but led to a more than four-fold increase of the shelf life of sea bass, as compared to the untreated samples.