نشریه بهره برداری و پرورش آبزیان
سال دوم شماره 3 (پاییز 1392)

The structural properties of the outer layer of the battered and breaded products is important because the maximum amount of oil absorbed was occure from the pores of the this foods. The aim of this study was investigated the effect of shape products (nugget and finger) and particle size of breading coated (particle size small, medium and large) on the sensory and quality properties of fish finger and fish nugget produced from silver carp. After preparation, the dough product was molded in two cube-shaped (finger) and round (nugget) than were covered with three differents particle size of breading (particle size small, medium and large). The treatments (three nugget (N1, N2, N3) and three finger (F1, F2, F3)) were examined undergone the chemical, physical, and sensory experiments. The effects of shape products (finger and nugget) were showed significant difference on the fat content, pH, products yield and shrinkage and the particle size of breading have significant different on the batter pick-up and breaded pick-up, pH and color (p˂0.05), and the combined effects of shape and particle size of breading were significant effects only on the water-holding capacity (p˂0.05). The moisture content of both factors was not significant (p˃0.05). The higher amount of fat was abserved in fish finger, whereas the fish nugget was showed the higher levels of pH, products yield and shrinkage. The large breading particle saize displayed the highest products yield, breaded pick-up, pH, redness and yellowness index and the lowest of lightness index (p˂0.05). Treatments that coated with smaller breading particle size have smoother and more uniform coating and by increased particle size the surface roughness was increased. Generally accepted fish finegrs that coated with large particle size breading was higher than other treatments.

gold fish (Carassius auratus gibelio) is from the family of cyprinidae wich like common carp (cyprinus carpio). While there are many examples of the use of estrogens to skew sex ratios in fish few address teleost species and none have been published for the gold fish, Carassius auratus gibelio. vitellogenin is a big glicolipophosphoprotein that synthesis from liver under 17-b estradiol hormone.fingerlings of gold fish feeding by 17b estradiol to 6 mounths in 3 dose (10 25 50) mg per kg plus control treat. estradiol resolve in etanol then spray on food. in 25 and 50 mg per kg E2 all female fish product. with high in dose of E2 metabolism and growth of fish reduce.

In this study antioxidant activity of the red algae (Hypnea hamulosa) was investigated in the Invitro condition. The measurement included total phenolic content, ferric reducing power, DPPH radical scavenging activity and total antioxidant activity. Seaweed samples with the ratio of 1:20 (algae: solvent) were extracted using conventional solvent extraction method for 24 hours. The applied solvents were pure water (100%) and organic solvents ‘i.e’ ethanol, methanol and acetone with the ratios of 30%, 50%, 70% and 100%. The results indicated that acetone extracts (50%) had the highest values in the total phenol contents, ferric reducing antioxidant power, DPPH radical scavenging activity and total antioxidant activity with the values of 0.27, 0.06 mg tannic acid / g algal powder, 69.98% and 0.07 mg ascorbic acid/ g of dry algal, respectively. Acetone 50% was the best solvents and ratio to determine antioxidant activity of this alga. From the results it can be concluded that the Persian Gulf red algae seems to be an appropriate species for phenolic extraction. However differences found in the antioxidant activity between solvent ratios may be related to the solvents polarity and biochemical properties of the algae.

the antioxidant activity of pomegranate seed oil on common kilka oil (Clupeonella cultriventris caspia) was reported in this work. The D-optimal Mixture Design using Design-Expert® (Stat-Ease Inc.¡ MN/USA) version 6 was applied for experimental design. The effects of pomegranate seed oil at different concentrations were studied (0.0¡ 0.07¡ 0.15¡ 0.22 and 0.3 percentage) on oxidative stability in fish oil after storing for 7 days at 45 °C and were compared to the control sample. The antioxidant activity was assessed by determination of the peroxide¡ thiobarbitoric acid¡ free fatty acid and conjugated diene values. The result indicated that the antioxidant activity increased with the increasing pomegranate seed oil concentration from 0.07 – 0.22 % and pomegranate seed oil at 0.22 % exhibited the highest antioxidant activity.
This study indicated that pomegranate seed oil is an appropriate natural antioxidant to stabilize and to preserve fish oil quality. Pomegranate seed oil might be suggested to be used as a substitute for synthetic antioxidants in fish oil industry.

organophosphate insecticides such as diazinon are common to control pests in many agricultural fields that are located in the vicinity of fresh water resources. In this study Male Goldfish were exposed for 10 days at concentrations of 3 and 6 mg/ l Diazinon (granules 10%) and after that Histopathological effects of diazinon on some fish tissues were examined by light microscope. According this study some focal degeneration and necrosis of tubules in kidney, hyperplasia and adhesion in secondary lamella in gills were observed. No histopathological sign in gut were observed in fish treated toxin.The histopathological changes significantly increasedas toxin concentration increased.