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971.
Aqueous and ethanol extracts of Acacia pennata (bark), Catunaregam uliginosa (fruit), Diospyros lenceofolia (fruit), and Sapindus mukorossi (fruit) were evaluated as piscicides on the freshwater fish Danio dangila, Danio rerio, and Puntius shalynius, and the air-breathing Heteropneustes fossilis. Catunaregam uliginosa (fruit) possessed relatively higher piscicidal potency followed by Sapindus mukorossi (fruit), Acacia pennata (bark), and lastly Diospyros lanceofolia (fruit). Catunaregam uliginosa can thus be used for eradicating unwanted wild fishes in a short time span at low concentrations so that the health of aquatic environment is maintained. 相似文献
972.
Toke Koldborg Jensen Jette Nielsen Erling P. Larsen Jens Clausen 《Journal Of Aquatic Food Product Technology》2013,22(3-4):214-226
Mathematical models for simulating and optimizing aspects of supply chains such as distribution, planning, and optimal handling of raw materials are widely used. However, modeling based on a holistic chain view including several or all supply chain agents is less studied, and food-related aspects such as quality and shelf-life issues enforce additional requirements onto the chains. In this article, we consider the supply chain structure of the fish industry. We discuss and illustrate the potential of using mathematical models to identify quality and value-adding activities. The article provides a first step toward innovative supply chain modeling aimed to identify benefits for all agents along chains in the fish industry. 相似文献
973.
《Journal Of Applied Aquaculture》2013,25(3):19-32
ABSTRACT Effects of three diets: (1) complete diet; (2) supplemental diet (vitamin and mineral supplements not added); and (3) the supplemental diet with an adjunct organic fertilization regimen (using distiller's dried grains with solubles [DDGS]) on benthic macroinvertebrate populations and water quality in experimental ponds used to culture freshwater prawns, Macrobrachium rosenbergii were investigated. Benthic samples were taken from deep (1.5 m) and shallow (1.0 m) areas of each of nine 0.02-ha ponds every three weeks, using a 0.09-m2 Ekman dredge. The abundance of gastro-pods, oligochaetes, total non-insects, chironomids, total dipterans, total insects, and total macroinvertebrates was significantly higher (P <0.05) in ponds receiving the complete diet, possibly due to lower predatory pressure by prawns or direct benefits of micronutri-ents. Total macroinvertebrate abundance was significantly decreased (P <0.05) in ponds receiving supplemental diet (with and without organic fertilization), possibly due to increased predation by prawns to supplement the nutrition not provided by the lower quality diet. Organic fertilization significantly increased (P <0.05) the abundance of oligochaetes and total macroinvertebrates. These data suggest that M. rosenbergii can adjust to reduced feed quality by increasing consumption of benthic fauna. 相似文献
974.
The effect of frozen storage temperature on quality-related parameters of rainbow trout (Oncorhynchus mykiss) muscle was studied in the interval from ?10 to ?80°C on samples stored for 1 to 18 months. The following quantities were measured: drip loss, water holding capacity and water distribution, color, lipid oxidation (thiobarbituric acid-reactive substances, TBARS), and membrane stability (enzyme activity). No effect of temperature on drip loss, water holding capacity, water distribution, or membrane stability was observed for samples stored below ?20°C, whereas storage at ?40°C or lower compared to ?30°C or higher resulted in a reduced level of secondary lipid oxidation (TBARS). No advantage was gained by using temperatures below ?40°C for frozen storage of trout regarding any of the properties investigated. 相似文献
975.
Qiancheng Zhao Irek Klonowski Magnea G. Karlsdottir Sigurjon Arason 《Journal Of Aquatic Food Product Technology》2013,22(3):258-269
Fish gelatine and protein solutions prepared from saithe by-products were injected into saithe fillets. Effects on weight changes, water holding capacity, and chemical composition of the fillets were investigated after chilled (2, 5, and 7 days) and frozen (14 and 49 days) storage. The results showed that higher weight yields were obtained by adding proteins and salt to the fillets in comparison with only salt, especially in chilled fillets. The drawback of the injection was that higher drip losses were found during storage and thawing than for untreated fillets. Effects of injection on water content were only significant after 2 days of chilled storage, but differences leveled out after longer storage time and with freezing and thawing of the fillets. The procedure applied in this study seems to be promising for utilization of by-products such as trimmings as an ingredient in higher value products like fillets, in comparison to mince products. 相似文献
976.
Shahrooz Taheri AbbasAli Motallebi Ali Fazlara Ashot Aghababyan 《Journal Of Aquatic Food Product Technology》2013,22(3):310-321
Antioxidants have been widely used as additives to provide protection against oxidative degradation of foods by free radicals. The effect of thyme essence (Zataria multiflora Boiss) on the rancidity development in cobia (Rachycentron canadum) fillets during frozen storage was studied. Cobia fillets were treated with thyme essence (250 and 500 ppm) and then stored at??18°C for up to 6 months. Rancidity development was measured by several biochemical indices including free fatty acids (FFA), peroxide value (PV), thiobarbituric acid (TBA), and complemented by sensory analysis (flesh odor, consistency, and appearance). Also, pH and expressible moisture were measured during 6-month storage. Proximate composition was also determined in the first day. TBA, PV, and FFA levels increased in all treatments due to lipid oxidation. Thyme essence showed an antioxidative effect in cobia fillets during frozen storage as indicated by TBA, PV, and FFA levels. Results showed that FFA, primary and secondary oxidation products, expressible moisture (EM), and pH of thyme essence treated samples were significantly lower than those of the control samples (p < 0.05). Thyme essence retarded oxidative changes in frozen cobia fillets, and the best oxidation inhibition was obtained using thyme essence at 500 ppm. 相似文献
977.
Themistoklis Altintzoglou Wim Verbeke Filiep Vanhonacker Joop Luten 《Journal Of Aquatic Food Product Technology》2013,22(2):103-119
This study investigated the effect of balanced, nonpersuasive information related to safety, healthiness, and sustainability of aquaculture on the image of farmed fish among European consumers. It was demonstrated that there is neither positive nor negative influence of this type of information on the predominantly positive image of fish from aquaculture. Consumers who were exposed to information related to the EU origin and aquaculture related guarantee reported a more positive image of farmed fish. These results provide valuable input for transparent communication about fish farming practices which might increase consumer trust and will not harm the image of fish from aquaculture. Increasing consumers' knowledge about aquaculture and its positive effects on the image of farmed fish is also discussed as a pathway for maintaining and improving aquaculture's positive image in the future. 相似文献
978.
Gareth Kituu Chris Kanali Douglas Shitanda Charles Njoroge Joseph Mailutha 《Journal Of Aquatic Food Product Technology》2013,22(4):555-567
ABSTRACTStudies were undertaken to establish the performance of a genetic algorithm-optimized solar tunnel dryer in drying of fish by comparing quality attributes of fish dried in the optimized solar tunnel dryer with that dried in a nonoptimized solar tunnel dryer and in open sun. A two-way analysis of variance revealed a highly significant difference between moisture ratios for the fish dried under the optimized solar tunnel dryer and the other methods (F = 53.59, Fcrit,1% = 4.09). In addition, thiobarbituric acid reactive substances showed that fish dried in the optimized dryer did not develop rancidity (2.30 µg MA/kg), that dried in nonoptimized dryer approached rancid values (5.3 µg MA/kg), while open sun dried fish was slightly rancid (7.95–8.45 µg MA/kg). Further, based on total volatile base nitrogen, fish under the three drying treatments did not develop significant putrefaction. Furthermore, it took 15, 22, and 28 h to dry fish to equilibrium moisture content of 0.12 kg/kg (dry basis), for the optimized and nonoptimized solar tunnel dryers and for the open sun drying, respectively. Thus, the optimized solar tunnel dryer is superior to both nonoptimized solar tunnel dryer and open sun drying in the drying of fish. 相似文献
979.
ABSTRACTYogurt is a traditional dairy product widely consumed all over the world. Syneresis, which is a result of lower water holding capacity, is a big concern and an important quality parameter. In this study, the efficiency of locust bean gum and different gelatins (fish skin, fish scale, and bovine skin) in preventing syneresis was investigated. Samples were stored at 4°C for 2 weeks, a typical shelf life of yogurt, and analyzed periodically for quality parameters. Syneresis, viscosity, and water holding capacity of the control and gum added samples were almost identical, while gelatin added samples were generally significantly improved (p < 0.05). 相似文献
980.