• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.3
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• pp.378-383
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• 1995

Phospholipid(PL), phosphatidylcholine(PC) and phosphatidylcholine free PL(PCF) were extracted from squid viscera and the antioxidant effects of each fraction on the oxidation of refined fish oil were evaluated. Polyunsaturated fatty acid contents were the highest in PC(46.7%) followed by PL(44.8%) and PCF(40.9%). The effects of each phospholipid fraction on stabilizing fish oil were compared by incubating at 40$^{\circ}C$ for 10 days. At the initial period(2 days), changes in peroxide value did not show any significant difference ; however, as incubation time was extended, PC fraction showed the strongest antioxidant activity. PL and PCF added to fish oils also resulted in increased stability against oxidation. Antioxidative effect of PC at the 5% level was equivalent to 0.05% BHT, 1% catechin and 1% tocopherol.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.1
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• pp.98-104
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• 1995

To utilize the mackerel viscera effectively, antioxidant substances were extracted and the effects on the oxidation were evaluated. Total lipid(TL) extracted from mackerel viscera were fractionated into hexane extracts, tetracarbon chloride($CCl_4$)-methanol(1 : 1, 1 : 3, 1 : 9, v/v) extracts, phospholipid(PL), phosphatidylcholine(PC), and PC free fracitons(PCF). Inhibition of fish oil oxidation was investigated using these fractions. Hexane fraction showed lower antioxidant activity compared to the TL or $CCl_4-methanol$ fractions(C-M) ; in addition, antioxidant activities increased as polarity of C-M increased. Significant antioxidant activities were observed with PL, PC, and PCF ; among them, PC was the most effective. To determine the antioxidant activity of PC, effects of natural or synthetic antioxidant were compared. Addition of PC to fish oil proved to enhance antioxidant activity the antioxidant activity of phospholipids was derived mainly from PC.

• Korean Journal of Food Science and Technology
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• v.26 no.2
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• pp.123-126
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• 1994

Changes in lipid components of pollack meat during sun-drying and effects of NaCl on lipid oxidation were examined. TBA values and peroxide values of sun dried pollack(SD), salted and sun dried pollack (SS) were 0.142 and 14.8 meq/kg, 0.226 and 20.0 meq/kg after sun-drying, respectively. Raw pollack contained 6.12% total lipid consisted of 2.42% neutral lipid(NL) and 3.70% phospholipid(PL) as dry basis, and there were $47{\sim}65%$ decrease in PL content during sun-drying. The NL class of raw pollack mainly consisted of triglyceride(TG), sterol(ST)+diglyceride(DG), hydrocarbon(HC)+sterol ester(SE), and main components in PL class were phosphatidylcholine(PC), phosphatidylethanolamlne(PE) and phosphatidylserine(PS). The contents of TG, ST+DG, PC and PE decreased, while those of free fatty acid, HC+SE, sphingomyelin and lysophosphatidylcholine increased markedly during sun-drying. The major fatty acids of TL in raw pollack, PD and SD samples were generally 22:6, 16:0, 20:5, 18:1 and 18:3; 20:5 decreased markedly during sun-drying, while saturates and monoenes such as 16:0, 18:0 and 18:1 increased slightly. And remaining ratios of polyunsaturated fatty acids of TL, NL and PL in SD and SS samples were 81.1%, 92.5%. 73.3%, and 74.6%, 74.1%, 45.4%, respectively. The results of changes in lipid components during sun-drying showed that sodium chloride catalyzed the lipid oxidation of pollack meat during drying processing.

• Korean Journal of Food Science and Technology
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• v.29 no.3
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• pp.437-445
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• 1997

Studies were carried out to investigate the changes of lipids in chestnut (Castanea crenata Sieb. et Zucc) during storage at $20^{\circ}C$ for 9 weeks and $1^{\circ}C$ for 15 weeks. Lipid composition of fresh chestnuts were 43.4% of nonpolar lipid (NPL), 26.5% of glycolipid (GL) and 30.1% of phospholipid (PL) in total lipid (TL). Nonpolar lipid was composed of triglyceride (TG), 1,2-diglyceride (1,2-DG), 1,3-diglyceride (1,3-DG), sterolester (SE), sterol (S) and free fatty acid (FFA). Main constituents of glycolipid were digalactosyldiglyceride (DGDG), monogalactosyldiglyceride (MGDG), sterylglycoside (SG), and acylsteryglycoside (ASG). Main constituents of phospholipid were phosphatidylcholine (PC), phosphatidylethanolamine (PE) and phosphatidylinositol (PI). The content of nonpolar lipid was decreased after 5 weeks of storage, and glycolipid content was increased during 7 weeks and then decreased. Phospholipid was the most increased lipid during storage at $20^{\circ}C$ and $1^{\circ}C$. The contents of TG, SE, S, DGDG and MGDG were increased during storage at $20^{\circ}C$ and $1^{\circ}C$. The major fatty acids were linoleic acid, oleic acid, palmitic acid and linolenic acid in TL, NPL, GL, PL, TG, DG, ASG, PC and PE. The content of palmitic acid was relatively higher in the PL. Linoleic acid among them was increased during storage at $20^{\circ}C$ and $1^{\circ}C$, while oleic acid was decreased.

• Korean Journal of Food Science and Technology
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• v.18 no.2
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• pp.153-157
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• 1986

Changes in lipid components of Gae-bul, Urechis unicinctus, during hot-air drying ($40^{\circ}C$, 7 hrs) were studied. Raw sample contained 1.3% total lipid (TL) which consisted of 35.1% neutral lipid (NL), 18.0% glycolipid (GL) and 46.9% phospholipid (PL), and dried sample contained 5.3% TL which consisted of 51.8% NL, 20.5%GL and 27.7% PL. There were about 40% decrease in PL content and a slight increase in NL content during drying. The NL of raw sample mainly consists of triglyceride (TG, 39.8%), free sterol (FS, 39.6%), free fatty acid (FFA, 12.2%). and also identified diglyceride (DG), monoglyceride and esterified sterol and hydrocarbon in less quantify. The percent of TG and FS decreased, while that of FFA and DG increased during drying. And main components in the PL were phosphatidyl choline (PC,45.6%), phosphatidyl ethanolamine (PE,34.8%), and followed by phosphatidyl serine (PS) and an unknown substance. In the components of PL, PE, PS and PC decreased slightly in order during drying. And major fatty acids of raw and dried samples were generally 16:0, 18: 1, 18:3, and 20:5. The content of the polyenoic acid such as 20:5 decreased. while the saturated acid increased slightly during drying.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.4
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• pp.217-224
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• 1988

Changes in lipid components of Gul-bi, salted-dried yellow corvenia, during processing and storage were studied. Raw fishes contained $6.7\%$ total lipid (TL) which consisted of $83.3\%$ neutral lipid (NL), $6.5\%$ glycolipid (GL) and $10.2\%$ phospholipid (PL), and salted-dried sample at 30 days storage contained $11.1\%$ TL which consisted of $86.1\% NL, $7.1\%$ GL and $6.8\%$ PL. The NL was mainly consisted of trigly ceride (TG), free sterol (FS), free fatty acid (FFA), and the main lipids in PL were phosphatidyl choline (PC), phosphatidly ethanolamine (PE) and sphingomyelin (SPM). The contents of TG, PC, PE decreased, while that of FFA, SPM increased during processing and storage. Total fatty acid contents of raw fish, salted sample, salted-dried sample (product) and product at 30/days of storage were 847.9, 764.0, 633.5 and 588.mg/g-lipid, respectively, taking $C_{23:0}$ as the internal standard material. Most fatty acid con tents of TL revealed a tendency to decrease during processing and storage, highly unsaturated fatty acid such as $C_{22:6},\;C_{20:5}$, decreased largely. The major fatty acids in TL, NL, GL and PL were generally $C_{16:0},\;C_{16:1},\;C_{18:1},\;C_{20:5},\;C_{22:6}. Percentage of $C_{16:1},\;C_{18:1}$ in NL and GL and GL are higher than those in PL, while $C_{22:6},\;C_{20:5},\;C_{20:4}$. Peroxide value in salted-dried sample is 121.6 meq/kg and decreased rapidly with storage period, carbonyl value and brown pigment formation showed tendency of increase during processing and storage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.14 no.4
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• pp.419-427
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• 1985

The properties of lipids in cap and stalk of 'Koshin' (Shiitake, Lentinus edodes, withxpanded cap) were studied. It was also carried out that the characteristics of lipids in fresh 'Donko'(unexpanded cap) and the changes of lipids in those samples by various drying process. The total lipid (TL) content in the cap and stalk of 'Koshin' were 4.58% and 2.65% respectively. It was found that the contents of neutral lipids (NL, $46.7{\sim}48.8%$) and phospholipids (PL, $42.0{\sim}43.8%$) were high, while that of glycolipids(GL, $9.2{\sim}9.5%$) was low. The main lipid in NL was triacylglycerol (TG, $58.0{\sim}58.5%$) followed by sterolester (SE, $16.9{\sim}17.4%$), sterol (ST, $15.6{\sim}16.4%$), diacylglycerol (DG, $5.8{\sim}6.0%$) and monoacylglcerol (MG, $1.1{\sim}1.3%$). The main lipids in PL was phosphatidyl ethanolamine (PE, $58.3{\sim}6.02%$) followed by phosphatidyl choline (PC, $17.3{\sim}19.5%$), cardiolipin (CA, $12.8{\sim}14.0%$) and lyso-phophatidyl choline (LPD, $4.8{\sim}6.6%$). Fatty acid composition was significantly different among TL, NL, GL and PL contained in cap and stalk. The main fatty acids was $C_{18:2}$ followed by $C_{16:0}$ and $C_{18:1}$ acids. The TL contents in cap and stalk of fresh 'Donko' were 3.7% and 2.5%. The changes of TL contents, PoV by drying were not almost observed. AV(acid value) of TL in the sun dried samples was a little lower than those of the fresh and hot air dried samples, on the contrary NL content in TL of the former was a little higher than those of the latters. The main lipid in NL of the three samples was TG followed by SE, ST, DG, MG and free fatty acid (FFA). In the above lipids, FFA contents in NL of the sun dried sample was a little higher than those of the fresh and hot air dried samples, but TG content in NL of former was a little lower than those of the latters. The main lipid in GL of the three samples was digalactosydiglycerol (DGDG) followed by acylsterylglucoside(ASG), sterylglucoside (SG), monogalactosyldiglycerol (MGD) and cerebroside (CER). Influence of drying on these lipid content were nol almost recognized. The main lipid in PL of the three samples was PE followed by PC, CA, LPC and phosphat idyl serine (PS). In the above lipids, PE and PC contents in PL of the sun dried one were a little lower than those of the fresh and hot air dried ones. The main fatty acid in TL, NL, GL and PL of the three samples was $C_{18:2}$ followed by $C_{16:0},\;C_{18:1}$. The $C_{18:2}$ acid contents of the sun dried sample was a little lower than those of the fresh and hot air dried ones, while $C_{16:0}$ content of the former was a little higher than those of the former was a little lower than those of the latters.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.3
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• pp.241-249
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• 1993

The class and fatty acid composition of neutral lipid(NL) and phospholipid(PL) of Korean sweetfish were experimented. The NL was mainly consisted of triglyceride ($94.8{\sim}99.5\%$), and also identified free sterol($0.29{\sim}2.77\%$), sterol ester and diglyceride in less quantity. Triglyceride content of viscera was much higher than those of other tissues. Main components in the PL were phosphatidylcholine(PC, $7.9{\sim}61.6\%$), phosphatidyl ethanolamine(PE, $19.3\%{\sim}39.3\%$) and followed by diphosphatidyl glycerol and sphingomyelin. PC and PE contents were higher in muscle and head tissues. The major fatty acids in NL fractions of sweetfish were 16:0, 18:1n-9, 16:1n-7, 18:2n-6, 18:0 and 14:0. Fatty acid composition of NL was similar to those of total lipid and were not significantly different among the fishes, the large and small sweetfish. In case of PL fractions, the major fatty acids were 16:0, 18:1n-9, 22:6n-3, 18:0 and 18:2n-6.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.22 no.1
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• pp.19-24
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• 1989

Changes in lipid components of powdered Katsuobushi during processing such as boiling, smoke-drying were examined. The total lipid (TL) in raw skipkack was $1.8\%$ and it consisted of $79.2\%$ neutral lipid (NL), $7.8\%$ glycolipid (GL) and $12.5\%$ phospholipid (PL), while powdered Katsuobushi product showed $4.5\%$ TL which consisted of $82.5\%$ NL, $9.2\%$ GL and $8.3\%$ PL. The contents of triglyceride, digalactosyl diglyceride, phosphatidyl choline and phosphatidyl ethanolamine decreased when free fatty acid, diglyceride and monogalactosyl diglyceride increased during processing. Also formation of Iysophosphatidyl choline was identified in PL of product. Total fatty acid contents of raw fishes, boiled sample, 1st smoked sample and powdered Katsuobushi were 721.8mg, 589.8mg, 549.6mg and 473.1mg expressed in $C_{23:0}$ as the equivalents of fatty acid contents. Most fatty acid contents of TL revealed a tendency to decrease during processing, there were about $43\%$ decrease in polyenes, $36\%$ decrease in monoenes, and $26\%$ decrease in saturates quantitatively. The major fatty acids in TL, NL, GL and PL of samples were generally $C_{16:0},\;C_{18:0},\;C_{16:1},\;C_{18:1},\;C_{20:5}$ and $C_{22:6}$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.39 no.5
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• pp.376-383
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• 2006

The chemical components, lipid class, and fatty acid composition of the viscera from male and female common squid, Todarodes pacificus, were examined to evaluate the possible utilization of the liver, reproductive organs, and gills. In male and female squid, the viscera comprise 21% and 27% of the body weight, respectively. The protein content of the viscera was slightly higher in females (17.7-19.5%) than in males (15.6-17.2%). This was especially marked in the female reproductive organs, while there was little difference in the gill. The liver contained the largest amounts of lipids (17.2-18.6%) and the levels were higher in males than in females (P<0.01). By contrast, the reproductive organs of females contained more lipids than did those of males (4.68% vs. 1.65%, p<0.01). The prominent non-polar lipid (NL) classes were triacylglycerol (51.9-55.4% of the NL content) and sterol ester (16.3-21.8%) in the liver, and free sterol (47.0-68.5%) and free fatty acids (31.5-41.2%) in the reproductive organs. However, there were no significant differences in the NL classes between sexes. The percentage of the most prominent phospholipid (PL) class, phosphatidylcholine (PC), was highest in the liver (78.1-79.6% of the PL content), and there was no significant difference between the sexes. By contrast, phosphatidylethanolamine (PE) was highest in the reproductive organs (33.4%), and was higher in males than in females (P<0.05). All the visceral organs contained 36.4-48.5% of n-3 polyunsaturated fatty acids (PUFA), such as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). The DHA level was highest in female reproductive organs (32.3%), while EPA was high in male reproductive organs. These results demonstrate that the viscera of male and female common squid are a good source of DHA and EPA.