• The Korean Journal of Food And Nutrition
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• v.10 no.1
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• pp.14-24
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• 1997

The seasonal variation in lipids, and fatty acid composition of neutral lipid(NL) and phospholipid(PL) contained in the muscles of hibernant fish(loach) were investigated. In the investigation, four groups of wild loaches ere used, those caught May, 1993(before spawning period), August, 1993(after spawning period), November, 1993(just before hibernation) and March, 1994(just after hibernation). The NL was the most abundant in muscle lipid, followed by PL and glycolipid(GL), and also the composition and variation patterns were almost similar between female and male throughout all the periods. NL content began to increase gradually after March and came to the maximum in August(under 90%) ; hereafter got to decrease gradually again and came to the minimum in March of the next year(under 60%). While the variation-pattern of GL and PL was in inverse proportion with that of NL and their content came to the maximum in March of the next year. The NL and PL fractions were mainly consisted of triglyceride and phosphatidyl choline respectively, and both of the contents showed the highest value in August, the lowest in March of the next year. The major fatty acids in NL fraction were 16:0, 16:1, 18:1, 18:2 and 18:3($\omega$3). In particular, the ratio of 16:1 was much higher than that in PL, while those of highly unsaturated fatty acids(HUFAs) such as 20:4($\omega$6), 20:5($\omega$3) and 22:6($\omega$3) were much lower. The ratio of 16:0 in NL was almost constant through the year, however those of 16:1, 18:1, 18:2 and 18:3($\omega$3) showed a tendency to increase after March and were about 2~4% higher in May, compared with that in March, while those of HUFAs were about 2~4% lower. In particular, the ratio of 16:1 in NL continuously decreased after May and markedly decreased in March of the next year, but those of 18:1, 18:2 were almost constant until November. In August, saturates and monoenes were higher levels due to the slight increase of 18:0, 14:1 and 17:1 than in the other periods, while those of HUFAs decreased and the unsaturation(TUFA/TSFA) of NL showed the lowest value in August. On the contrary, saturates and monoenes gradually decreased after November and the most of them including 18:0, 16:1, 18:1 and 18:2 rapidly decreased in March of the next year, while 20:1, 20:4(~6), and 20:5(~3), and 22:6(~3) were in inverse proportion. PL consisted mainly of 16:0, 16:1, 18:1, 18:2, 20:4(~6), and 20:5(~3). Saturates and monoenes-composition showed almost no difference in March and May, while polyene acids ratio showed similar changes with that of NL. In August, the ratio of saturates(16:0, 18:0) were high but that of HUFAs were low, and after November 16:0, 18:0, 18:1, 18:2 and 18:3($\omega$3) began to decrease, while most of HUFAs increased in their composition-ratio until the marking increase of their unsaturation and the big changes of 18:2, 18:3($\omega$3), 20:4($\omega$6), 22:6($\omega$3) in March of the next year.

• Journal of Fisheries and Marine Sciences Education
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• v.3 no.2
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• pp.47-72
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• 1991

To obtain the principal data for useful treatment and processing of Korean geoduck (Panope japonica A. ADAMS) which inhabit mostly at Dong-Hae coastal area in Korea, changes of $NH_2$-N, TMAO, TMA, total creatinine, protein composition and fatty acid composition in raw and blanched geoduck muscle during storage at $-20^{\circ}C$ were investigated. In addition, its chemical composition variation in the whole year was elucidated. The moisture content in geoduck muscle meat was 78.1% to 82% in the whole year. Particularly, in July its moisture content was maximum as 82% and in September minimum as 78.1%. Crude protein was in the range of 12.3-16.4%, crude lipid the average was 1.5%, crude ash on the average was 1.4%. The abundant fatty acids in geoduck muscle oil were $C_{16}$ : 0, $C_{16}$ : 1, $C_{18}$ : 0, $C_{18}$ : 1, $C_{20}$ : 5, and $C_{22}$ : 6 acids. During storage at $-20^{\circ}C$, content of unsaturated fatty acid such as eicosapentaenoic acid (EPA, $C_{20}$ : 5) and docosahexaenoic acid (DHA, $C_{22}$ : 6)in raw geoduck muscle decreased somewhat and the raw geoduck was slightly oxidized. Trimethylamine (TMA), volatile basic nitrogen (VBN)and $NH_2$-N of raw muscle increased compared to blanched muscle. Trimethylamine oxide (TMAO) was slightly decreased during the storage period. The muscle protein was approximately composed of 37% sarcoplasmic, 29% myofibrillar, 22% alkali soluble, and 12% stroma protein. Among several proteins, myofibrillar protein content decreased mostly, while the alkali-soluble and stroma protein content increased slightly during storage at $-20^{\circ}C$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.4
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• pp.333-343
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• 1984

This study was designed to elucidate the lipid and its fatty acid composition in various tissues of fresh water fishes. The free and bound lipids in meat, skin and viscera of crucian carp (Carassius carassius) were extracted with ethyl ether and the mixed solvent of chloroform-methanol-water (10/9/1, v/v). The free and bound lipids were fractionated into neutral lipid, glycolipid and phospholipid by a silicic acid column chromatography using chloroform, acetone and methanol, respectively, and quantitatively analyzed by thin layer chromatography (TLC) and TLC scanner. The fatty acid compositions of polar ana nonpolar lipids in meat, and these of neutral lipid in various tissues were analyzed by gas liquid chromatography(GLC). The free lipid content in meat, skin and viscera was $6.22\%,\;9.95\%\;and\;9.76\%$, whereas the bound lipid content in those tissues was $10.01\%,\;3.56\%\;and\;7.36\%$, respectively. The neutral lipid contents in free lipid were ranged from $71.7\%$ to $89.4\%$, and $3{\sim}9$ times higher than those in bound lipid, while the phospholipid contents in bound lipid were ranged from $42.3\%$ to $63.2\%$, and $5{\sim}10$ times higher than those in free lipid. The neutral lipid was mainly consisted of triglyceride ($81.91{\sim}88.34\%$) in free lipid, and esterified sterol & hydrocarbon ($41.00{\sim}59.43\%$) in bound lipid. The phospholipid was mainly consisted of phosphatidyl ethanolamine($54.56{\sim}66.79\%$) and phosphatidyl choline ($21.88{\sim}34.28\%$) in free lipid, and phosphatidyl choline ($50.49{\sim}70.57\%$) and phosphatidyl ethanolamine ($15.74{\sim}24.92\%$) in bound lipid. The major fatty acids of polar lipid in free and bound lipids were $C_{16:0}\;(17.53\%,\;19.29\%)$, $C_{18:1}\;(24.57\%,\;16.08\%)$, $C_{18:2}\;(8.39\%,\;4.03\%)$, $C_{22:5}\;(1.68\%,\;8.08\%)$, and $C_{22:6}\;(6.22\%,\;13.60\%)$ and these of neutral lipid in free and bound lipids were $C_{16:0}\;(17.67\%,\;24.15\%)$, $C_{16:1}\;(12.81\%,\;5.52\%)$, $C_{18:1}\;(24.13\%,\;13.02\%)$, $C_{18:2}\;(15.47\%,\;8.68\%)$, $C_{22:5}\;(0.88\%,\;4.14\%)$ and $C_{22:6}\;(1.17\%,\;5.04\%)$, respectively. The unsaturations (TUFA/TSFA) of polar lipid in free and bound lipids were 2.02 and 2.74, and $1.5{\sim}2.0$ times higher than 1.51 and 1.23 of nonpolar lipid. In both polar and nonpolar lipids, w3 highly unsaturated fatty acid (w3HUFA) content of bound lipid was $2{\sim}5$ times higher than that of free lipid. The polyenoic acid contents such as $C_{20:5},\;C_{22:5}\;and\;C_{22:6}$ in bound lipid were $2{\sim}5$ times higher than these in free lipid. Consequently, there were significant difference between the lipid and its fatty acid composition in free and bound lipids and/or in various tissues.