• The Korean Journal of Malacology
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• v.32 no.4
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• pp.269-277
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• 2016

We examined the seasonal variation of the proximate, amino acid, fatty acid composition and glycogen contents of triploid Pacific oyster cultured in western coastal waters of Korea in 2015. The specimens were collected in February, May, August and November from off-bottom farming site. The lipid content was the highest in winter season (February, $2.10{\pm}0.06%$), the protein content was the highest in autumn season (November, $9.09{\pm}0.04%$) while the moisture and ash content was the highest in summer season (August, $86.00{\pm}0.12%$ and $2.67{\pm}0.03%$, respectively). The total amino acid contents was the highest in winter season (1,011.5 mg / 100 g), decreased gradually and was the lowest in summer season (486.7 mg / 100 g). The total amino acid composition was dominated by taurine, aspartic acid, glutamic acid, glycine and alanine. In the fatty acid composition, the two fatty acids, eicosapentaenoic acid and docosahexaenoic acid, which comprised that as much as 50% of the total fatty acid contents, were dominated during all season. The glycogen content was the highest in summer season ($1.26{\pm}0.03g$ / 100 g) although it was stable during the other season with the range of $0.69{\pm}0.04-0.86{\pm}0.01g$ / 100 g. Taken together, these results suggest that triploid pacific oysters have high commercial value not only in winter season but in summer season because they do not spawn and have high contents of glycogen comparing with those of diploid oyster in this period.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.1
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• pp.170-176
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• 2002

The objective of this study was to investigate the current status of calcium fortification in processed foods for obtaining basic data on nutrition fortification policy and nutrition labeling, Surveyed samples were the products fortified wish calcium among processed products sold in department store and large mart in Seoul from Aug. 1998 to Aug. 1999. But supplementary health food or special nutritious food and weaning food and infant formula were excluded from them. We examined the kinds and numbers of added nutrients except calcium and the amounts of calcium per 100 g product and nutrient labeling of calcium-fortified foods. Surveyed products were 81 foods and they were grouped in grain products, milk and milk products, processed meat and fishes, ramyuns, retort pouch foods, fruit juice and drinks. and others. Calcium fortification was found in wide food groups, especially in snack foods and carbonated beverages. In relation to surveyed products, most of them were fortified with only calcium. The number of added nutrients in the product were relatively various in comparison with each food groups. In addition to calcium, the most frequently added nutrient was DHA, and were followed vitamin, mineral, oligosacchride, fiber, etc. This result showed that the kind(s) and the number(s) of nutrient added to product did not consider nutrition balance of calcium-fortified foods. Units of calcium content were decided by companies, therefore consumers confused labelled content with mouth dose of calcium and the comparison of the amounts added calcium among products was difficult. The amounts of calcium in products were from 16.4 to 1226 mg Per 100 and from 2.5 to 27.6% RDA (recommended daily allowance) per serving size. The amounts of calcium in many products were less than 10% RDA per serving size, whole appraisal about fortified content was needed. And for nutrient labeling on calcium, they used various term whether it is approved by law or not.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.3
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• pp.319-328
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• 1997

To develop a beneficial microbial feed for the cultivation of rotifer, Brachionus plicatilis, an aerobic photosynthetic bacterium, Erythrobacter sp. $S\;\pi-I$ was isolated from marine structure at Haeundae beach in Pusan, Korea. Feeding effects of Erythrobacter sp. $S\;\pi-I$ on the growth of rotifer were analyzed comparing to other feeds such as PSB (purple nonsulfur bacteria), Chlorella sp. and baker's yeast. Erythrobacter sp. $S\;\pi-I$ contained more linoleic acid $(C_{18:3\omega3})$ and oleic acid $(C_{18:1\omega9})$ and amino acids than PSB (purple nonsulfur bacteria), Chlorella sp. and baker's yeast. The rotifer fed on Erythrobacter sp. $S\;\pi-I$ showed better effects than those fed on other feeds in the individual growth, size and weight. Also, the rotifer especially contained more eicosapentaenoic acid $(C_{20:5\omega3})$ and docosahexaenoic acid $(C_{22:6\omega3})$ in case of Erythrobacter sp. $S\;\pi-I$ feeding than the other feeds. In case of the feed of PSB and baker's yeast docosahexaenoic acid $(C_{22:6\omega3})$ did not show. In amino acid analysis, the rotifer fed on Erthrobacter sp, $S\;\pi-I$ showed more amino acid content comparing to those fed on other diets. Especially, arginine, isoleucine, histidine, lysine, methionine, phenylalanine, threonine, which are essential amino acid for fish growth, showed high contents. These results suggested that the aerobic photosynthetic bacterium, Erythrobacter sp. $S\;\pi-I$ would be a beneficial microbial teed for the cultivation of rotifer.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.3
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• pp.380-388
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• 2005

Lipid characteristics of 6 species of fish frame (armored weasel-fish, AW; chum salmon, CS; spanish mackerel, SM; common mackerel, CM; conger eel, CE and skipjack tuna, ST) were studied by determining total lipid (TL) contents, lipid classes, and fatty acid composition. The highest yield of bone was obtained from ST frame (64.2%), followed by CS frame (57.9%), CE frame (54.6%), A W frame (41.6%), SM frame (41.7%), and CM frame (32.6%). The highest neutral lipid content was also found in total lipid (TL) from SM bone (23.3 g/100 g), followed by TL from CE bone (21.5 g/100 g), CS bone (16.0 g/100 g), and CM bone (15.5 g/100 g), while those from ST and A W bones were 7.2 g/100 g and 0.4 g/100 g, respectively. The prominent lipid classes of neutral lipids (NL) from all fish bones and muscles were triglyceride (TG), however, which was much lower in AW than in other fishes. The percentages of EPA and DHA in NL from fish bone were in the descending order of CS (29.3%), ST (27.1%), AW (27.0%), CM (25.7%), SM (21.6%), and CE (14.9%). Based on the lipid characteristics, the CS frame was the best resource for extraction of a functional lipid.

• Journal of Aquaculture
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• v.8 no.4
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• pp.355-366
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• 1995

In order to identify some suitable diatoms as a live food source, effects of seven diatom species (Chaetoceros simplex, Navicula incerta, Phaeodactylum tricornutum, Nitzschia closterium, Skeletonema costatum, Thalassiosira pseudonana, Thalassiosira weissflogii) were examined on specific growth rate, mean celt volume, chemical composition and general fatty acid composition. In cell volume. T. pseudonana was the smallest $(125{\mu}m^3)$ and T. weissflogii the largest $(824{\mu}m^3)$. However the specific growth rate of the largest diatom was the lowest (0.5016/day), and that of S. costatum was the highest (0.9928/day). The crude protein content of seven diatom species varied from $18.96\%$ (T. pseudonana) to $24,4\%$ (T, weissflogii). The crude lipid content of C. simplex was the highest $(8.43\%)$, and that of T. pseudonana was the lowest $(3.13\%)$. The total content of polyunsaturate fatty acids which are important for bivalve larvae was higher in C. simplex than those in other species. The total percent of polyunsaturate fatty acids from N. incerta and T. weissflogii was relatively lower than that from other species. Dietary value of seven diatom species were finally examined with Pacific oyster larvae Crassostrea gigas. In this experiment, C. simplex showed the highest survival rate and growth, and the larvae feed on S. costatum and T. weissflogii showed the poorest results. This results C. simplex could be more useful live food for bivalve larvae than other diatom species tested.

• Korean Journal of Poultry Science
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• v.41 no.1
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• pp.53-59
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• 2014

To evaluate the meat quality differences of Korean Native Chickens (KNC) available in Korean market, the physicochemical and sensory characteristics of a broiler and two KNC (HH and WD breed) were analyzed. The fat content of KNC WD breast meat was higher than that of KNC HH. The breast and thigh meats of KNC HH had higher $L^*$ and $a^*$ values than the broiler or the KNC WD. WD meats showed greater DPPH radical scavenging activity and higher pH values than the HH. For the fatty acid composition, there was no significant difference in total content of the saturated fatty acids among chicken breeds (p>0.05). KNC had greater content of polyunsaturated fatty acids, especially arachidonic acid (20:4) and DHA (22:6), compared with the broiler. KNC WD meats had higher composition of linolenic acid (18:3) than the KNC HH. For sensory evaluation, the WD breast meat showed higher taste and tenderness scores than the HH. On the other hand, the soup made by broiler had higher taste scores than the KNC. The breast and thigh meat from two KNC breeds showed different quality parameters that may come from the differences of genetic attributes, feed, and production strategy between two breeds.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.5
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• pp.436-445
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• 1986

As the second part of the studies on the utilization of polyunsaturated lipids in sardine oil as nutritional or medical supplement, the conditions of lipid extration and concentration, refining, and storage stability of EPA-condensed sardine oil were investigated. In extraction of lipids, solvent ratios of chloroform-methanol mixture(2:1 v/v) affected the final content of unsaturated lipid in extracted oil and recovery. Stepwise solvent fractionation method at various low temperatures was effective to concentrate polyenoic acids like EPA and DHA when acetone or acetone-methanol mixture, added in the ratio of 1:5 (v/v) was applied step by step to different temperatures at 0 to $-35^{\circ}C$. Addition of 1 to $5\%$ (v/v) of water to acetone was also benefit to raise EPA content but that resulted in reducing the yield of condensed oil from $65\%\;to\;28\%$. Concentration rate of polyenoic acids by solvent fractionation in lipid-actone solution (1:5, v/v) at 0 to $-30^{\circ}C$ seemed limited to $5{\sim}8\%$ in fatty acid composition depending on the initial content of those polyenoic acids in the sardine oil. During the extraction, concentration, and alkaline treatment, oxidation was rapidly induced but oxidation products could be thoroughly removed on the process of deceleration and peroxide elimination. To stabilize the reactive polyenoic acid condensed oil during the storage, stuffing nitrogen gas was essential to expel dissolved oxygen in oil or to seal the oil from open air, and the addition of antioxidative agents as BHA and tocopherols were greatly helpful to extend the storage life.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.5
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• pp.537-544
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• 2014

Kwamaegi is a traditional Korean seafood made from the flesh of Pacific saury Cololabis saira. It is recognized as a valuable, healthy food containing the ${\omega}$-3 fatty acids EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). This study was conducted in order to obtain basic data for application to the canning process of Kwamaegi using red pepper paste with vinegar. Commercial Kwamaegi was cut into $2{\times}3cm$ lengths and 90 g was put into cans (301-3). Then, 60 g of water was added and precooked for 10 minutes at $100^{\circ}C$. The water was drained after precooking. The precooked Kwamaegi was packed into cans, and 60 g of red pepper paste with vinegar was added. The cans were seamed using a vacuum seamer, then sterilized for differing times (8-12 minutes) in a steam system retort at $121^{\circ}C$. Parameters such as: pH, TVB-N, amino-N, total amino acid content, free amino acid content, color value (L, a, b), texture profile, TBA value, mineral content, sensory evaluation and viable bacterial count of the product produced under varying sterilization times (8-12 minutes) were measured. There were no remarkable differences between sterilization conditions and textural characteristics. The results showed that product sterilized for 8 minutes proved to be the most desirable.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.6
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• pp.869-879
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• 2012

This study was conducted to investigate the effects of dietary lipid source and level on growth performance, blood parameters, fatty acid composition and flesh quality of sub-adult olive flounder Paralichthys olivaceus. Eight experimental diets were formulated to contain 5% squid liver oil (SLO), 5% linseed oil (LO), 5% soybean oil (SO), a mixture of 1% squid liver oil, 2% linseed oil and 2% soybean oil (MIX), no lipid supplementation with high protein level (LL-HP), 10% squid liver oil (HL-SLO), a mixture of 1% squid liver oil, 4.5% linseed oil and 4.5% soybean oil (HL-VO), and 1% squid liver oil with high starch level (LL-HC), respectively. Two replicate groups of fish (average initial weight of 296 g) were fed the diets for 17 wks. After 5 wks, 11 wks and the end of the feeding trial, five fish from each tank were randomly sampled for analysis of body composition. At the end of the feeding trial, final mean weight of fish fed the LL-HP diet was significantly (p<0.05) higher than that of fish fed the HL-VO diet, but did not differ significantly from those of fish fed the SLO, LO, SO, MIX, HL-SLO and LL-HC diets. Fish fed the LL-HP diet showed significantly higher feed efficiency than fish fed the LO, HL-SLO and HL-VO diets. Feed efficiency of fish fed the LO, SO and MIX diets were similar to those of fish fed the SLO and HL-SLO diets. Fish fed the HL-SLO diet showed significantly higher total cholesterol content in plasma compared with other diets. Fatty acid composition of tissues was reflected by dietary fatty acid composition. The highest linoleic (LA) and linolenic acid (LNA) contents in the dorsal muscle were observed in fish fed the SO and LO diets, respectively, regardless of feeding period. The highest eicosapentaenoic acid (EPA) content in the dorsal muscle was observed in fish fed the LL-HP and LL-HC diets after 11 and 17 weeks of feeding, respectively. Fish fed the SLO and HL-SLO diets showed higher docosahexaenoic acid (DHA) content than that of other treatments after 11 and 17 weeks of feeding, respectively. Dietary inclusion of vegetable oils reduced n-3 HUFA contents in the dorsal muscle and liver of fish. The n-3 HUFA contents in tissues of fish fed the SLO and HL-SLO diets were higher than those of fish fed other diets, except for the LL-HP and LL-HC diets. Hardness, gel strength, chewiness and cohesiveness values of dorsal muscle in fish were significantly affected by dietary lipid source. The results of this study indicate that fish oil in fish meal based diets for sub-adult olive flounder could be replaced by soybean oil and linseed oil without negative effects on growth and feed utilization.

• Fisheries and Aquatic Sciences
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• v.4 no.4
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• pp.163-170
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• 2001

The effect of perilla oil added in diet on the biochemical properties of cultured sweet smelt, Plecoglossus altivelis, was investigated. The cultured fish were fed two different diets for 8 weeks; a control diet was a commercial diet, which was low in the content of docosa­hexaenoic acid (DHA, 22: 6n-3) and eicosapentaenoic acid (EPA, 20: 5n-3) less than approximately $2\%$ (CO group) and an experimental diet (PO group) was added perilla oil as a lipid source in the diet of the CO group. The PO group was superior in growth rate and feed efficiency compared with CO group. This trend showed markedly in female of both groups. The fatty acid composition in the muscle of PO group was closely related with those of the diet, while those of CO group were not. For plasma components, total cholesterol (CHOU of PO group was higher than that of CO group. Thiobarbituric acid-reactive substances (TBARS), hydroxyl (OH) radical levels and superoxide dismutase (SOD) activity of plasma were higher in PO group than CO group. The intensity of watermelon-like or cucumber-like aroma was much stronger in PO group with higher level of TBARS and OH radical in plasma compared CO group. Survival rate was also high in PO group with high levels of phagocytic rate, CHOL and SOD activity. These results suggest that perilla oil might be usefulness as a lipid source of the cultured sweet smelt diet, in which result in high quality of the cultured fish.