• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.3
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• pp.423-431
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• 2020

This study was conducted to investigate in vivo and in vitro digestibility in juvenile Atlantic Bluefin tuna Thunnus thynnus. In vivo digestibility was compared between four experimental diets to determine the optimum dietary inclusion level of an enzyme-treated sardine fish meal (EFM) and sardine fish meal (FM). The experimental diets were as follows; EFM75 (75% EFM), EFM60 (60% EFM and 15% FM), FM75 (75% FM) and SL (frozen sand lance) as a raw fish feed. Feces of Bluefin tuna (90.3 g) were collected both by siphoning from a 700 L cage and by dissection in 69 ton concrete rearing tanks. For the siphoning method, protein digestibility was higher in the tuna fed SL diet than that of other groups. The lowest protein digestibility was observed in FM75. For the dissection method, protein digestibility was higher in tuna fed EFM75 diet than that of other groups. The lowest protein digestibility was observed in the EFM60 group. In vitro digestibility was compared in six protein sources to find an alternative source of EFM for the tuna feed. The highest in vitro digestibility was observed in EFM (92%) followed by low temperature FM (72%), meat meal (65%), feather meal (60%), sardine fish meal (57%) and poultry by-product meal (55%).

• Animal Bioscience
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• v.36 no.9
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• pp.1414-1425
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• 2023

Objective: Long chain n-3 polyunsaturated fatty acids (PUFA) exert positive effects on human health. The long chain n-3 PUFA of pork can be increased by adding fish oil to the diet. Due to the cost and availability of fish oil an alternative source must be found. Methods: This study evaluated the effect of five dietary oils on meat quality, fatty acid composition and lipid stability. The five diets contained 1% palm oil (Control), 1% soya oil, 1% linseed oil, 1% fish oil, and 1% Echium oil, respectively. The trial consisted of 60 gilts, randomly allocated to five groups. Results: All color parameters, extractable fat content, fat free dry matter, and moisture content of the m. longissimus muscle were unaffected by dietary treatment. Consumers and a trained sensory panel could not detect a difference between the control samples and the Echium oil sample during sensory analysis. Samples containing higher levels of PUFA (soya, linseed, fish, and Echium oil) had higher levels of primary and secondary lipid oxidation products after refrigerated and frozen storage. However, these values were still well below the threshold value where off flavors can be detected. The Echium oil treatment had significantly higher levels of long chain PUFA than the linseed oil treatment, but it was still significantly lower than that of the fish oil treatment. Conclusion: Echium oil supplementation did not increase the levels of n-3 to the same extent as fish oil did. The result did however suggest that Echium oil can be used in pig diets to improve muscle long chain n-3 fatty acid content without any adverse effects on meat quality when compared to linseed, soya, and palm oil.

• Journal of Aquaculture
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• v.8 no.4
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• pp.261-269
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• 1995

A practical control diet was prepared and compared with raw fish ($80\%$ frozen horse mackerel + $20\%$ commercial binder meal) and moist pellet ($50\%$ frozen horse mackerel + $50\%$commercial binder meal) diets to develop a practical diet formulation for Korean rockfish (Sebastes schlegeli). Korean rockfish averaging 68.5g were fed with the three experimental diets for 11 months. Final average body weight was approximately 330g and showed no significant difference between fish groups (P>0.05). Feed efficiency of fish from control diet was significantly lower than those of fish from raw fish and moist pellet diets (P<0.05). Protein and lipid retention efficiency of fish ranged $26.9-28.8\%$ and $86.5-110.2\%$, respectively, without any significant difference between the different diets. At the end of the experiment, chemical composition for the various parts of fish body and flesh quality of the raw fish were examined. The data showed that there was no significant difference between fish from the different diet groups for moisture, protein and lipid contents of whole body, liver, and dorsal muscle. Also, thirty three panelists did not find any difference in color, smell, texture, and taste of the raw fish flesh. These results suggest that Korean rockfish can be cultured with a laboratory practical feed without any negative effects on growth, nutrient utilization, chemical composition of fish, and quality of raw fish. Therefore, the next step in developing practical feed is to modify the control diet for improving fish performance and reducing feed cost.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.20 no.3
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• pp.191-201
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• 1987

Seasoned sardine meat was prepared to extend the use of sardine for human consumption, and processing conditions and storage stability of frozen seasoned sardine meat were studied during storage at $-20^{\circ}C$. The fish was beheaded, gutted and cleaned in a washing tank. The washed fish was then put through a belt-drum type meat separator which separates the flesh iron the bone and skin. Mechanically deboned fish meat was mixed with $20.6\%$ emulsion curd, $0.5\%$ table salt, $2.0\%$ sugar, $0.4\%$ sodium bicarbonate, $0.2\%$ polyphosphate, $0.1\%$ monosodium glutamate, $0.3\%$ onion powder, $0.1\%$ garlic powder, $0.1\%$ ginger powder, $3.0\%$ soybean protein and $0.1\%$. In sodium erythorbate. This seasoned sardine meat was frozen with contact freezer, packed in a carton box and then stored at $-20^{\circ}C$. The pH, volatile basic nitrogen, viable cell counts, peroxide value, carbonyl value, thiobarbituric acid value, taste compounds, fatty acid composition, salt extractable nitrogen, drip, texture, and color values of the products were determined during frozen storage. The results showed that lipid content in products could be controlled by using emulsion curd, and flavor and texture could be improved by adding spices and soybean protein, and lipid oxidation could be retarded by $0.1\%$ sodium erythorbate. Judging from the results of chemical experiments and sensory evaluation, the products can be preserved in a good quality for 120 days during frozen storage.

• The Korean Journal of Food And Nutrition
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• v.10 no.4
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• pp.553-558
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• 1997

Frozen cod fillet block(7.0$\times$4.6$\times$0.6cm, 18$\pm$0.5g) was purchased from a supermarket in Taegu area. Three experimental groups of fish fillet, frozen-thawed cod fillet refrigerated at 5$^{\circ}C$(R), frozen at -2$0^{\circ}C$(F) and repeated freezing and refrigerating(RFR) every other day, were incubated at each temperature. Changes in the viable counts of mesophiles and psychrotrops, the amount of free drip and pH of cod muscle during cold storage were 6.5$\times$104 and 7.4$\times$103 CFU/g of muscle, respectively. The viable counts of cod muscle R and FRF exceeded 107 CFU/g within 8 days and 16 days, respectively, while the viable counts of cod muscle F were not exceeded 107 cells/g throughout the storage period. The viable counts of psychrotrops exceeded that of mesophiles at the end of cold storage period. The viable counts of cod muscle showed positive correlation with pH(r=0.73-0.96,the highest in RFR) during cold storage. The amount of free drip in cod muscle R, F and RFR was 27.06$\pm$9.75, 27.56$\pm$8.02 and 33.97$\pm$10.70%, respectively. The amount of free drip in RFR increased as the progress of storage.

• Journal of fish pathology
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• v.34 no.2
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• pp.141-147
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• 2021

In this study, of the imported shrimps between 2017 and 2020, we investigated white spot syndrome virus (WSSV), covert mortality nodavirus (CMNV) and decapod iridescent virus 1 (DIV-1). Of the imported shrimps (a total of 29 groups), WSSV was detected as 31% (9/29) by nested PCR assay. And CMNV and DIV-1 were not identified in this study. To investigate the genetic relatedness of WSSV identified from imported shrimp, VR 14/15 region showed WSSV genomic variable loci was compared with reference isolates. Among the nine WSSV-positive samples, VR 14/15 region was amplified in only a sample (20-CH-1 isolate, imported from China in 2020). And the 20-CH-1 isolate showed 99.8% identity with WSSV-IN-05-01 which was reported in India in 2005, suggesting that those of WSSV have been spread from India to China. Furthermore, although the pathogenicity of WSSV identified from frozen shrimp was not evaluated, the international trade of diseased frozen shrimps could be led to the potential risk of virus transmission.

• Food Science and Biotechnology
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• v.17 no.1
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• pp.199-202
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• 2008

The effects of $\beta$-(1,6)-galactosyl trehalose trisaccharide ($\beta$-GT) that was preferentially produced by Escherichia coli $\beta$-galactosidase on cryo- and thermo-protections of protein were investigated with those of other sugars at the level of 8% (w/v). As compared to a control without sugar additive, $\beta$-GT effectively enhanced 32-54% of the cryoprotection of fish actomyosin against repeated freeze-thawing and frozen storage, and also 49% of the protection against thermal inactivation of pyrophosphatase, respectively. As a result, it was significantly more effective than sorbitol and trehalose in both cryoprotection and thermoprotection. Thus, $\beta$-GT would be possibly applied as a sugar substitute for cryo- and thermo-protective applications of food protein.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.11 no.1
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• pp.1-3
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• 1978

When frozen sandeel Ammodytes personatus which had been stored for a long time, was given to yellowtail for 70 to 80 days, some mortality of the rearing fish began to appear. The liver of the diseased fish showed some yellowish brown discoloration and histopathological study revealed that fatty degeneration of the liver cells was obvious, and this degeneration was especially heavy around bile-duct. The cell nuclei showed atrophy.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.1
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• pp.170-183
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• 2015

The objectives of this study is to analyze the competitiveness of fisheries trade between Korea and China, and to estimate strategic seafood export products for Korea-China FTA in fisheries sector. The results of analyses indicate that Korea has comparative advantages in export items such as spanish mackerel, flatfish, cod, roe in frozen fish(0303), and squid, sea cucumber, oyster in molluscs(0307). In addition, tuna in prepared or preserved fish(1604), sea cucumber in crustacean, molluscs and other aquatic invertebrates(1605) have comparative advantage in exporting to China.

• The Journal of Fisheries Business Administration
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• v.53 no.4
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• pp.51-67
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• 2022

The Korean tariff rate for fishery products is a single tax rate of 10% for live fish and frozen seafood, and 20% for all others. Since FTAs have been concluded with several countries, the tariffs is not an appropriate means to protect domestic fishery producers. The differential tariff rate according to the scientific name (genus) of the fishery products, which was implemented 30 years ago to protect fishery products produced in the Korean coastal waters has lost its original purpose. It seems that future fishery trade policy should focus on IUU prevention, hygiene and safety of consumers rather than protecting fishery producers through customs tariffs. This paper suggest that a paradigm shift in the fishery producers protection policies such as direct financial support from the state, protection and development of fishery resources, and support for fostering the 6th industry rather than indirect protection through tariffs.