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The effect of different essential oils on the quality and shelf life of fish and seaweed burgers during storage was evaluated. For this purpose, thyme and oregano essential oils were selected at a concentration of 0.05% (v/w). Three types of salmon and seaweed burgers were prepared: without essential oil, burgers with red thyme essential oil (0.05% (v/w)) and burgers with oregano essential oil (0.05% (v/w)), which were vacuum packaged and stored at 4 °C for 17 days. Physicochemical and microbiological analyses were carried out periodically throughout storage. The addition of both essential oils did not have any effect on the evolution of the pH, the moisture content or texture parameters. Only the thyme essential oil managed to slightly slow down the increase of total volatile basic nitrogen and trimethylamine nitrogen. The samples with oregano essential oil and especially those with thyme essential oil showed minor oxidation. The salmon and seaweed burgers without essential oils and those which contained oregano essential oil showed a faster increase of mesophilic counts than those which had thyme essential oil, but no noticeable improvement was observed in the shelf life of the burgers with thyme essential oil. To improve the shelf life of the fish and seaweed burgers, it would be necessary to increase the concentration of both essential oils. [ABSTRACT FROM AUTHOR]

The objective of this work was to study the effect of partial sodium replacement by potassium and packaging conditions on the physicochemical properties of smoked sea bass during cold storage. Sea bass fillets were salted with 100% NaCl (Na samples) or with 50% NaCl–50% KCl (Na:K samples), smoked, packaged under three different conditions (air, vacuum and modified atmosphere) and stored at 4 °C for 42 days. Physicochemical parameters, color and texture were periodically determined in the raw material and in smoked samples during cold storage. The smoking process led to a reduction in moisture, pH and aw values, and an increase in water holding capacity, ash and mineral contents. Smoked fish exhibited significant differences in color and texture as compared to fresh fish. The type of packaging had an effect on the pH, water holding capacity and texture. Samples in air exhibited the highest pH values and water holding capacity in these samples gradually decreased during storage. Textural parameters decreased during storage in samples packaged in vacuum and modified atmosphere. The pH of Na samples was initially higher than in Na:K samples, and this difference remained over the rest of the study. The type of salt did not affect the texture or other physicochemical parameters. [ABSTRACT FROM PUBLISHER]

The aim of this work was to determine the proximate composition and physicochemical parameters of different smoked and marinated fish to provide a database with the typical values of the parameters which best define these products. Three batches corresponding to different purchase dates of 15 commercial products were analyzed. Great variability in all parameters was observed between products and between batches of a same product, e.g., in smoked anchovy, NaCl contents varied from 7.1 to 11.8% (w/w), which led to a wide variation in the aw (from 0.877 to 0.931). These important differences found in moisture, NaCl contents, pH, aw, water holding capacity, and color, between batches would affect product shelf life and its sensory features. This variability implies that the consumer expectations would not be met. For this reason, producers should adjust the processing parameters in order to obtain smoked and marinated fish with homogeneous characteristics. PRACTICAL APPLICATIONS This study deals with the composition and physicochemical characterization of different smoked and marinated fish products available in the market. For these kinds of products, certain physicochemical parameters are directly related to shelf life and sensory characteristics. In this sense, the aw decrease, the NaCl content increase, and/or the pH reduction are the main responsible for prolonging the shelf life of these products. On the other hand, salt content, water holding capacity and color have an important impact on the sensory attributes, which have direct implications for consumers' acceptability. An accurate knowledge of the typical values of the main characteristics in smoked and marinated fish would allow the parameters which best define these products to be standardized, providing a reference for producers and researchers in the field of new product development. [ABSTRACT FROM AUTHOR]

The objective of this work was to study the evolution of the volatile fraction, and ATP and its breakdown products, in desalted cod thermally treated (water blanching, steam blanching and microwave heating), stored at 4 °C. All analyses were carried out at 0, 7, 14, 21, and 28 days of storage, as in the treated samples as in the control samples (desalted cod without thermal pre-treatment). The study of the volatile fraction revealed a similar behavior of the water blanched and steam blanched samples, by one hand, and of the control samples and those treated with microwave, on the other hand. This fact would imply a lower effectiveness of the microwave treatment on the preservation of the initial odor of desalted cod. The initial K1-values were lower in control and microwave samples than in water and steam blanched samples. However, the higher increase of K1-values throughout the storage in control and microwave samples would indicate a higher spoilage for these samples during the studied period. According to these results, the two blanching treatments were more effective than microwave heating in the preservation of desalted cod. [ABSTRACT FROM AUTHOR]

The objective of this work was to study the influence of the presence of skin, as well as the effect of size, thickness, initial weight and salting time on the dry salting kinetics of European sea bass, in order to characterise the salting process to obtain a lightly salted product. Fillets salted by the skin side showed lower salt gain and water and weight losses, which would indicate the barrier effect of skin on mass transfer. Processing time, contact area, initial weight and volume had significant effect on weight loss. Meanwhile, only processing time and initial weight were significant variables for water and NaCI weight changes, however thickness, contact area and volume were not significant due to the high effect of initial weight. However, it could be considered that thickness, contact area and volume had an indirect effect on mass transfer because initial weight was directly related to these variables. Salt diffusivity value in samples salted on the flesh side (7.54 X 10-11 m2/s) was similar to that reported in other studies. [ABSTRACT FROM AUTHOR]

BSTRACT: To reduce the microbial load of ready-to-use desalted cod, 2 different concentrations of sodium chloride (3.13% and 5.78% in water phase), potassium sorbate (0.14% and 0.20% in water phase), and citric acid (pH 6.10 and 5.77), with 2 kinds of packaging procedures (air or vacuum), have been used. The vacuum packaging was effective only in the samples with 3.13% salt after 28 d of storage, whereas no important differences between both packaging procedures were observed in samples with 5.78% salt. This last salt level only limited the Pseudomonas growth, however it was necessary to combine this salt concentration with potassium sorbate plus citric acid to inhibit mesophilic, psychrotrophic, and molds and yeasts. [ABSTRACT FROM AUTHOR]