• Korean Journal of Ichthyology
• /
• v.6 no.2
• /
• pp.99-131
• /
• 1994

The taxonomic revision of the flounders of the suborder Pleuronectoidei was made based on the specimens collected from the coasts of the Korean Peninsula from 1989 to 1993. The flounders of Korea are composed 34 species belonging to 24 genera and 4 families, and the keys to species, genera and families are provided with redescriptions and distributions. Three species of the flounders are found to be new to Korea : Tarphops oligolepis (Bleeker) of the family Paralichthyidae, Parabothus kiensis (Tanaka) of the family Bothidae and Pleuronectes pallasii Steindachner of the family Pleuronectidae. Laeops lanceolata, previously recorded in the Korean fish list, was found to be synonym of L. kitaharai. The fishes of the families Paralichthyidae and Bothidae were distributed in the Yellow Sea and the southern coast of Korea, while most of the flounder species of the family Pleuronectidae except Limanda yokohamae, Eopsetta grigorjewi, and Pleuronichthys cornutus were found along the eastern coast of Korea. It appears that Korean flounders are similar to those of Chinese and Japanese faunas which include tropical and temperate species without endemics.

• Korean Journal of Food Science and Technology
• /
• v.20 no.6
• /
• pp.878-882
• /
• 1988

The lipid components of cultured bastard(Paralichthys olivaceus) were analyzed and compared with those of wild one and flounder(Pleuronichthys cornutus). Total lipid(TL) content of dorsal muscle in wild and cultured bastard, flounder was 2.0%, 1.6%, and 1.9%, respectively. Wild bastard and flounder were higher in neutral lipid(NL) and glycolipid(GL) contents, while lower in phospholipid(PL) content than those of cultured one. The NL was mainly consisted of triglyceride(70.7-72.6%), and PL was mainly occupied by phosphatidylcholine(53.6-58.3%), phosphatidyl-ethanolamine(25.9-29.5%). In fatty acid composition of TL, cultured bastard showed higher content in polyenes such as docosahexaenoic acid. and lower in monoenes such as palmitoleic, oleic acid than those of wild one. Flounder was higher in Percentage of arachidonic, eicosapentaenoic acid compard with bastard. The major fatty acids of these fishes were palmitic, docosahexaenoic, oleic, eicosapentaenoic and palmitoleic acid in order. These fatty acid composition of NL, GL and PL fractions were not significantly different among wild and cultured bastard, flounder.

• Korean Journal of Food Science and Technology
• /
• v.20 no.6
• /
• pp.873-877
• /
• 1988

Nitrogenous extractives and amino acids were analyzed with the dorsal muscle from wild and cultured bastard(Paralichthys olivaceus), and flounder (Pleuronichthys cornutus). Cultured bastard was higher in moisture content, and lower in crude lipid and protein content than those of wild one. Contents of free amino acids from wild and cultured bastard, flounder were 305.03mg/100g, 253.42mg/100g, and 340.10mg/100g, respectively. The profile of free amino acids in these samples was very similar, although there were a relatively difference in glycine, threonine, proline contents. Content of IMP in wild bastard (408.31mg/100g) and cultured one (356.26mg/100g) were higher than that of flounder (178.61mg/100g). Wild bastard contained higher trimeth-ylamine oxide and total creatinine than cultured one. Total amino acid contents of dorsal muscle from wild and cultured bastard, and flounder were 21.94g/100g, 20.12g/100g, and 17.63g/100g, respectively. The major amino acids of these samples were glutamic acid, aspartic acid, leucine and isoleucine.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.41 no.4
• /
• pp.241-247
• /
• 2005

The aim of this study was to develop a trawl escapement device which can improve the survival rate of young fishes passed through trawl codend. The sea experiments according to the bar space of the device and bar materials were carried out to decide the bar space and device materials in Korean southern sea and off Cheju island. Stainless pipes and MC bars were used to test the efficiency of escapement device materials. Although escapement rates of MC bar for main species were a little higher compare with stainless pipe, the efficiency of device for stainless pipe was better than MC bar. Escapement devices of sort-K type and grid panel type were also compared. Escapement rates of redlip croaker(Pseudosciaena polyactis), blackthroat seaperch(Doederleinia berycoides) and finespotted flounder (Pleuronichthys cornutus) showed 61.7%, 2.0% and 2.7% on the sort-x type and 69.9%, 1.1% and 2.0% for the grid panel type but the difference was little. Fishes under 20mm head width and fishes which swimming speed is so slow compared with body length could not go through well the device. Escapement rates according to the bar space were estimated using grid panel type. The rates of redlip croaker(Pseudosciaena polyactis) for the bar space of 20mm, 25mm, 35mm were increased as 60.3%, 61.0% and 77.8%, and 9.8%, 16.4% and 45.6% for horse mackere1(Trachurus japonicus), respectively.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.46 no.4
• /
• pp.302-312
• /
• 2010

In order to describe the performance of a wedge type jellyfish excluder device, a series of fishing experiments was carried out in the coastal areas of Yokji Island, southern Korea in 2009, using a trawl net with a cover net. The body size and weight of each individual (fish or jellyfish) caught in the experimental fishing were measured. In the case of giant jellyfish the bell diameter and weight were measured. The catch species was composed of giant jellyfish (Nemopilema nomurai), silver croaker (Pennahia argentata), yellow croaker (Larimichthys polyactics), finespotted flounder (Pleuronichthys cornutus), largehead hairtail (Trichiuruslepturus), melon seed (Psenopsisanomala) and so on. The weight ratio and individual ratio of total fish escaped through the outlet of the excluder device were 0.322 and 0.320, respectively. The weight ratios of giant jellyfish excluded from the trawl net ranged from 0.740 to 0.921 (average 0.852/haul). It means that the wedge type jellyfish excluder device performed well and allowed the most of the giant jellyfish to exclude through the trawl net. The approximately 70% of fish entered in trawl net was caught. The wedge type excluder device needs some improvements to minimize the fish escape from the trawl nets in the future.

• Journal of Life Science
• /
• v.25 no.11
• /
• pp.1280-1289
• /
• 2015

Fish-meat gel is being produced mostly relying on surimi and raw materials imported from Southeast Asia and North America and present in small amount in local markets. In this study, common farmed local fishes were examined as stable and reliable sources of surimi for fish-meat gel production. For testing, five main farmed-fish of Korea, namely; Bastard halibut (Paralichthys olivaceus), Red sea bream (Pagrus major), Korean rockfish (Sebastes schlegeli), Common mulle (Mugil cephalus), and Finespotted flounder (Pleuronichthys cornutus) were used following a traditional washing process. The quality of the surimi was determined by the values of water content, whiteness index, gel strength and impurity. Accordingly, fish-meat gel and surimi quality experiments were carried out by measuring compressive and texture properties, expressible moisture content, Hunter color scale values and SDS-page protein patterns. Also gel characteristics were compared with that of FA and RA grade surimi (Alaska Pollock). Fish-meat gels were prepared by salt mincing the farmed-fish surimi with NaCl (2% w/w) and moisture adjustment to 84% by ice water adding. Prepared fish-meat paste was filled into 20-25 cm long polyvinylidene chloride casings and heated at 90℃ for 20 min. The whiteness values of fish-meat gels produced from surimi were increased by using farmed-fish and became comparable to that of FA Alaska Pollock gel. Among all tested farmed-fish, P. olivaceus and P. major exhibited better properties than RA Alaska Pollock and similar properties to FA Alaska Pollock. Therefore, current data suggests that fish farming can be an efficient and sustainable fish-meat source for fish-meat gel production in Korea.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.19 no.5
• /
• pp.493-501
• /
• 1986

The present work aims to estimate the effect of heat treatment on the in vitro protein digestibility and formation of trypsin inhibitor or trypsin indigestible substrate(TIS) of raw and defatted flounder. It was also carried out to assess the formation of lipid-protein complexes under the conditions of different ratio of lipid addition. The in vitro protein digestibility increased when steamed for 5 min showing $88.09\%$ in raw and $90.56\%$ in defatted samples, respectively. After 40 min steaming, the digestibility decreased by $2{\sim}4\%$. As for microwaving, heating for 1 min resulted in slight increase of digestibility, however, heating for 7 min did decrease of digestibility by $3{\sim}4\%$ for both raw and defatted materials. There was no difference in fatty acid composition found with heat treatment. The major fatty acids of flounder meat were $C_{16:0},\;C_{16:1},\;C_{18:1},\;C_{20:5},\;C_{22:6}$ and the ratio of the unsaturated to saturated was 67.3:32.6. Fat oxidation and nonenzymatic browning were enhanced by heat treatment and protein solubility decreased necessarily as the brown pigment formation increased. On the other hand, the effects on the digestibility and TIS of the complexes formed from interaction of lipid and myofibrillar or meat protein of flounder were examined. The interaction of protein with lipid was considered to mostly contribute to the drop of digestibility of fish products. The digestibility of myofibrillar protein was $93.72\%$ for flounder, and it generally decreased as the amount of lipid added to protein and reaction time increased. Also mixed and heated samples were more active in digestibility decline than those mixed after heating. The result probably indicated that lipid-protein interaction was involved in the drop of digestibility which coincided with protein denaturation.