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The aim of this study was to determine proximate compositions and sensory evaluation of tilapia meat. For this purpose, farmed Nile tilapia and Red tilapia were collected from the Inland Saline Waters Aquaculture Research Center located in Bafgh, Yazd. Fish were transported to Aquatic Fish Processing Research Center. Fatty acid composition, protein, fat, moisture, ash and sensory evaluation in fish meat were analyzed. Results showed that the tilapia meat had 1.30–1.68% fat, 18.70-19.26 protein, 78-79% moisture and 1.34-1.8% ash. Twenty seven fatty acids were identified in the tilapia meat. Saturated fatty acids were found between 24.84–27.12%, mono-unsaturated fatty acids 36.14-39% and poly unsaturated fatty acids 32.38-38.12%. Amount of Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) was calculated between 0.50-0.63% and between 6.12-6.19%, respectively. Results of sensory evaluation showed highest score for sensory evaluation parameters (color, odor,texture, test and flavors).

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The effect of three different packaging methods including Modified Atmosphere Packaging (MAP), Vacuum Packaging and normal Packaging was investigated on the quality of Nile tilapia fresh fillets stored in the refrigerator's temperature. The packaged samples were examined for 10 days with regard to the changes in chemical (TVN, PV, pH), microbial (total viable count) and sensory evaluations. The results indicated that the samples packed in MAP condition had higher quality than that of other methods at the end of the storage period. In addition, the slower destructive impacts and microbial growth was observed in MAP. The results of present study suggest that packaging tilapia under MAP conditions results in the increase in the durability, storing, and distribution period for fillets.

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The aim of the present study was to determine the impact of replacing the fish oil by alternative lipid sources in diets for rainbow trout (Oncorhynchus mykiss) on growth, fatty acid profiles of muscle. Five isonitrogenous and isoenergetic semipurified diets were formulated containing 100% rice bran oil (RBO), 100% linseed oil (LO), 100% Soybean oil (SO) and a 1:1:1:1 rice bran, linseed, soybeen and fish oil mixture (MX) were compared to a pure fish oil (FO) diet. The diets were fed to apparent satiation twice a day to triplicate groups of 30 rainbow trout with an initial weight of 90g for 15 weeks at 12°C.At the end of the experiment, fillet samples were collected from fish for the measurement of fatty acid profile and fillet composition. Fish fed the FO diet had the highest weight gain over the experimental period (280.28 g), However no differences in growth rate and CF were observed across diet groups. Feed conversion ratios (FCR) ranged from 1.12 to 1.24. Significant difference in FCR was found in the group fed an FO diet. The fillet lipid concentrations and fatty acid composition of the fish were significantly affected by the experimental diets. Fish fed the FO diet contained significantly lower lipid levels (20.18%) than those fed the 4 other diets. The highest level of n-3 PUFA concentrations were recorded in fish fed the LO diet (21.8) with significant difference than other diets and the lowest were in those fed the RBO diet (7.84). Fish fed the SO diet contained significantly higher level of n-6 PUFA concentrations (31.72) than other diets and the lowest were in those fed the FO diet (19.15). Fish on the FO diet had a significantly greater percentage of DHA (10.10%) in muscle tissue compared with fish on all other diets and the lowest was in those fed the RBO diet (2.81%). However, the highest level of eicosapentaenoic acid (EPA) concentrations was recorded in fish fed the SO diet (1.84%) and the lowest in those fed the diet (0.67%). This study showed considerable reductions (about 3-fold) in the n-3/n-6 ratio when FO in the fish diet was replaced by rice bran and soybean oils, which may be extremely negative from a nutritional point of view. In other hand linseed oil had the highest n-3/n-6 ratio (0.91) that was comparable with fish oil n- 3/n-6 ratio (0.89). The results in this study imply that an appropriate mix of vegetable oils and FO can replace the sole use of FO in fish feeds.

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The present project was aimed at determining the content, quality, and purity of β-carotene extracted from Azolla filiculoides in the Anzali Wetland, comparing it with synthetic β-carotene, and measuring its economic value. One treatment had β-carotene derived from Azolla filiculoides in the Anzali Wetland through the alkaline hydrolysis method in the summer of 2014. Treatments were kept at 4 °C for one year. Synthetic β-carotene was used as the control. The quality of the treatments was assessed by applying some chemical tests, including the measurement of the content and quality of β-carotene, colorimetry using the Hunter-LAB method, determination of the purity and vitamin A employing high-performance liquid chromatography (HPLC), estimation of the dwell-time duration at 5 °C, and measurement of the solubility of β-carotene in water. The results of the tests regarding the purity, concentration, colorimetry, vitamin compounds, dwell time, and solubility in the experimental β-carotene, compared with those in the control, revealed no significant difference (p>0.05). Moreover, the factors showed no significant difference between the control and experimental treatments during the dwell time (p>0.05). The natural β-carotene had a good quality during the storage period at 5 °C for one year. Since there was no significant difference between the β-carotene derived from Azolla filiculoides and the synthetic one in terms of the chemical tests, purity, and dwell time, and since the natural β-carotene derived from Azolla filiculoides takes precedence over the synthetic one in terms of the economic value, it is recommended that natural β-carotene extracted from Azolla filiculoides be substituted for synthetic β-carotene in the food industry.

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In this article, the total concentration of toxic heavy metals such as lead (Pb), cadmium (Cd), mercury (Hg), and arsenic (As), which are mandatory elements of the World Health Organization (WHO) and the Food and Agriculture Organization of the United Nations (FAO), were determined to measure the health of the edible tissue of the Caspian Sea Rutilus kutum. 90 samples of Rutilus kutum were collected in three northern provinces (Gilan, Mazandaran, and Golestan) during 2021-2022. The concentration of Pb, Cd, Hg, and As of Caspian Sea Rutilus kutum samples were prepared by standard method and acid digestion. All samples were analyzed using flame, graphite furnace, and cold steam of the atomic absorption spectroscopy instrument. The results showed that 90^% of all data samples (90^th percentile) concentration of toxic metals in Rutilus kutum tissue decreased in the order of Cd >As>Hg>Pb. The amounts of Cd, As, Pb, and Hg in Rutilus kutum tissue were observed at not detected-0.31, 0.001-0.15, 0.001-0.060, and 0.001-0.020 mg/kg wet body weight, respectively. Also, the statistical analysis showed that two types of correlations were found between the concentration of metals and the total length and weight of Rutilus kutum: for Cd with total length (r=-0.46) and with fish weight (r=-0.51), for As with total length (r=0.30) and with fish weight (r=0.27), It showed negative and positive, respectively, but mercury and lead metals did not show correlation with biometric parameters. Comparing the current results with international standards showed that the four toxic metals Cd and As, Pb, and Hg were lower than the FAO and WHO standards concentration. The findings showed that the health risk assessment parameters (EDI, HQ, and THQ) for all metals were much lower than the recommended values. This showed that the consumption of Caspian Rutilus kutum in the study area did not have any adverse effects on human health due to the contamination of toxic metals.