• Journal of the Korean Society of Food Culture
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• v.2 no.1
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• pp.25-31
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• 1987

We have examined to evaluate the taste compounds of damchi-jeotguk(concentrated sea mussel extract) which is a kind of traditional processed sea food in Korea. The contents of such compounds as free amino acids, nucleotides their and related compounds, non-volatile organic acid and fatty acid composition were analyzed. The content of total free amino acids was 10520.5mg/100g on dry basis and the major ones were glycine, arginine, aspartic acid and glutamic acid. These amino acids were resulted as 55.7% of total free amino acids in damchi-jeotguk. Hypoxanthine was the highest content($8.77\;{\mu}mole/g$, dry basis) of nucleotides and their related compounds. Free amino acid-N was the most abundant, resulting 53.3% of extractive nitrogen which was 3490.2mg/100g on dry basis and next ammonia-N, nucleotide-N and TMAO-N in order. The major non-volatile organic in damchi-jeotguk were succinic acid(125.5mg/100g, dry basis) and lactic acid 91.9mg/100g, dry basis). In this fatty acid composition of total lipid, polyenoic acid was abundant holding 45.5%. The major fatty acids were 16 : 0, 18 : 2, 22 : 6, 18 : 1 and 20 : 5. It was concluded from the omission test and chemical analysis that the major taste compounds of damchi-jeotguk were free amino acids and non-volatile organic acids.

• Fisheries and Aquatic Sciences
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• v.8 no.2
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• pp.43-50
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• 2005

We evaluated the nutritional composition of the siphon of the surf clam Tresus keenae in regard to the presence of nitrogenous [amino acids, nucleotides and their related compounds, total creatinine, betaine, trimethylamine oxide (TMAO), and trimethylamine (TMA)] and non­nitrogenous compounds (sugars and organic acids), lipid fatty-acid composition, and occurrence of minerals. The content of total free amino acids was 660.27 $\pm$ 7.94 mg/100 g, and the predominant amino acids were arginine, alanine, sarcosine, glycine, and glutamic acid. These amino acids accounted for $71\;\%$ of the total free amino acids. Among the nucleotides and their related compounds, inosine was the major component and comprised 40.38 $\pm$ 0.02 mg/100 g. Free amino acids were the largest contributor to total extracted nitrogen, comprising $49.94\%$, followed by total creatinine, betaine, nucleotides, and ammonia; the contribution of TMAO and TMA was small. For the non-nitrogenous compounds, malic acid, propionic acid, and succinic acid comprised the major portion of the ten kinds of organic acids detected, and the sugars found were glucose, maltose, and arabinose, which were estimated to be $147.0\pm7.15,\;34.45\pm1.09,\;and\;1.21\pm0.02\;mg/100\;g,$ respectively. The predominant minerals were Na and K, which comprised $11.43\pm1.06\;and\;9.46\pm1.02\;mg/100\;g,$ respectively. The major fatty acids were C22:6, C20:5, C23:0, C18:3, and C16:0 in the lipid fractions. The 23:0 level of glycolipid (GL) was the highest of any other lipid fraction. The amount of total polyunsaturated fatty acids (PUFA) in the lipid fractions was higher, ranging from $58.22\%\;in\;GL\;to\;77.1\%$ in phospholipid (PL), compared to the saturated and monounsaturated fatty acids. Of the n-3 fatty acids, C20:5 and C22:6 contributed $35.30-64.44\%$ of PUFA in the lipid fractions. The ratios of n-3 to n-6 PUFA in total lipid (TL), neutral lipid (NL), PL, and GL were 4.35, 4.26, 6.69, and 2.04, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.13 no.1
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• pp.27-31
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• 1980

Yellow sea bream, Branchiostegus japonicus, has been one of the widely consumed food fish in Jeju-Do, Korea. This study was attempted to establish the basic data for evaluating changes of taste compounds of the yellow sea bream during dehydration. The free amino acids were analysed by amino acid autoanalyser. The free amino acid composition of the raw yellow sea bream, abundant amino acids were lysine, alanine, threonine and arginine and then taurine, serine, proline, glycine, glutamic acid, leucine in order. Such amino acids as valine, methionine, tyrosine, isoleucine, phenylalanine were poor in content. The changes of free anino acid composition in the extract of the yellow sea bream during dehydration was not found. In the extract of dried product, lysine, alanine, glutamic acid and arginine were dominant holding $18.4\%,\;14.7\%\;8.0\%\;and\;7.3\%$ and $7.3\%$ of total amino acids respectively. The amount of total free amino acids of the yellow sea bream increased to more than 1.4 times during dehydration process, that of raw sample especially aspartic and glutamic acids increased to more than 2.9 times and 2. 1 times whereas taurine and histidine decreased ranging $40-50\%$ of the original content. It is presumed that the characteristic flavor of dried yellow sea bream was attributed to such amino acids like lysine and alanine known as sweet compounds, glutamic acid as meaty taste and TMAO known as plain sweet taste.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.11 no.1
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• pp.13-18
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• 1978

The present study was conducted to elucidate the pattern in changes of trimethylamine oxide and related compounds in the muscle of Alaska pollack during drying, especially referred to formaladehyde and dimethylamine. Three kinds of dried samples of Alaska pollack, sun dried, hot-air dried, and salted-sun dried, were prepared and analyzed for their contents of trimethylamine oxide, trimethylamine, dimethylamine, and formaldehyde. The amount of trimethylamine oxide remained in the salted-sun dried sample was relatively higher than those in the other two samples. In the content of trimethylamine, the hot-air dried sample showed an exceedingly high value shelving forty-two times higher than the raw sample while the other two samples showed barely three to four times content based on the raw sample. The dimethylamine content in the hot-air fried sample was comparatively lower than those in the other two samples, the former marked about ten folds of the raw sample's and tile latter showed about fifteen folds, respectively. Refering to the content of formaldehyde, it decreased to eighty-three percent of initial content in the hot-air dried sample. On the contrary, it increased about two times initial content in the other two samples, respectively. As a tendency, the formaldehyde content appeared increased or decreased correlatively with the dimethylamine content, whereas the case was reverse for the trimethylamine content.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.3
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• pp.215-222
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• 1994

Kang-Nung sik-hae is a traditional Korean fermented fish product which has remained in existence in Kang-Nung district. In order to preserve the traditional culture of Kang-Nung sik-hae and develop it as a commercial product, the property changes of sik-hae were investigated at different fermentation temperatures and periods. The chemical changes during the fermentation of squid(Todarodes pacificus) sik-hae were studied at different fermentation temperatures and periods. The amounts of proximate compositions and salinity did not change significantly at all fermentation temperatures and periods. The value of pH decreased with increasing storage period at all fermentation temperatures except at $5^{\circ}C$, whereas that of lactic acid at all fermentation temperatures increased. The amount of total arginine increased slightly up to 10-day of storage and decreased after that. The amount of $NH_2-N$ increased rapidly up to 15-day of storage at all temperatures and increased slightly after that. The amount of TMAO decreased significantly at $15^{\circ}C\;and\;20^{\circ}C$ and slightly at $5^{\circ}C\;and\;10^{\circ}C$, whereas that of TMA increased significantly at $20^{\circ}C$ up to 5-day of storage and decreased slightly after that. At all experimental temperatures except $5^{\circ}C$, the amount of TMA increased or fluctuated in proportion to the increase in fermentation periods. Inosine and hypoxanthine were the main components of nucleotides and their related compounds during the fermentation of sik-hae. Summarizing the above results, the optimum fermentation period of sik-hae was concluded to be 15-days at all experimental temperatures except $5^{\circ}C$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.4
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• pp.357-365
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• 1994

The effects of garlic concentrations on the properties of squid sik-hae such as the chemical and microbial changes were investigated. pH, the amounts of lactic acid showed significant differences at early stages of fermentation and no significant differences at later stages with increasing garlic concentrations. The amount of TMAO decreased with increasing storage periods and garlic concentrations, whereas that of TMA increased significantly at early stages of fermentation and showed no significant differences with increasing garlic concentrations. At later stages of fermentation, the amount of TMA at $2\%$ garlic concentration was higher than those at 3 and $4\%$. The number of lactic acid bacteria increased significantly garlic concentrations at early stages of storage and had no significant differences at later stages. The numbers of proteolytic bacteria, psychrotroph, and fungi increased in proportion to length of storage and garlic concentrations at early stages of storage whereas, the number of bacteria decreased significantly at later stages of storage with increasing garlic concentrations.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.4
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• pp.366-372
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• 1994

The effects of red pepper and grain contents on the properties of squid sik-hae fermented at $20^{\circ}C$ were investigated. The values of pH at $10\%$ red pepper contents and $30\%$ grain contents were lower at early stages of storage than $5\%\;and\;50\%$, respectively, and showed no significant differences at later stages of storage. The amounts of lactic acid and amino-N were not changed significantly at different red pepper contents where as, higher at $30\%$ grain content than at $50\%$ at early stages of storage. The amounts of total arginine were a little higher at $10\%$ red pepper and $30\%$ grain contents than at $5\%\;and\;50\%$, respectively. There were no significant effects of red pepper and grain contents on the amounts of TMAO and TMA during fermentation. Therefore, the effects of red pepper and grain contents on the chemical properties of squid sik-hae during fermentation were not significant.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.2
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• pp.111-119
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• 1993

The nitrogenous compounds and minerals in the raw and cooked meat of cockle shell were analyzed, and compared with those of cooked meat extracts. In abundant free amino acids, the content of glutamic acid was $129mg\%$ in raw meet, $105mg\%$ in cooked meat, $28mg\%$ in cooked meet extracts, aspartic acid, glycine, arginine, lysine, leucine, and alanine in order. The major components were lysine, arginine and leucine, and the minor components of essential amino acids were proline, tyrosine, serine and cystine. Some of ATP, ADP, AMP, inosine and hypoxanthine were identified in raw and cooked meat, but IMP and inosine were not detected in cooked meat extracts. A slight drop in content of ATP was showed in cooked meat and those had a higher content in inosine and hypoxanthine compared with raw meat. TMA, TMAO and betaine were also checked in all meat products and TMA slightly increased during cooking. Minerals in cooked cockle shell products were phosphorous, potassium, calcium and zinc. The content of phosphorous showed the highest value($16mg\%$ in raw, $185mg\%$ in cooked meat, and $25mg\%$ in extracts).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.2
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• pp.150-158
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• 1993

In order to investigate the content and seasonal variation of the extractive components including taste compounds, free amino acids, nucleotides and related compounds, quanternary ammonium bases, and guanidino compounds of ascidian collected from the south coast of Korea were determined bimonthy from April to October in 1990. The extractive nitrogen was composed of $60{\sim}62\%$ as free amino acids, $12{\sim}16\%$ as betaines, $5{\sim}9\%$ as nucleotides, and others as trimethylamine oxide(TMAO) and total creatinine. The muscle of ascidian was rich in such free amino acids as taurine, proline, glutamic acid, glycine and glycinebetaine. Most of nitrogenous compounds in the extractives showed a marked seasonal variation with a maximum in summer or autumn. AMP content was relatively high among nucleotides. Succinic acid, malic acid, lactic acid and pyroglutaric acid were the major organic acids in ascidian. The results of omission test suggested that the taste of ascidian is attributed to mainly free amino acid, betaines, nucleotides and nonvolatile organic acid in order.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.3
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• pp.252-255
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• 1999

The quality characteristics of the Korean traditional salt-fermented fish sauces, the traditional anchovy sauce (TAS) and the sandlance sauce(TKS) were evaluated comparing to the commercial anchovy sauce (CAS) and sandlance sauce (CKS). The acidity was higher in TKS than in TAS, whereas the contents of VBN, total-N and amino-N were higher levels in TAS. In color values, L and b values in TAS were generally higher than those in TKS, whereas a and ${\Delta}E$ values were higher in TKS. The contents of total free amino acids in TAS and TKS were $12.40\;g\%$ (w/v) and $9.549 g\%$ (w/v), respectively. The contents or six amino acids, alanine, glutamic acid, leucine, isoleucine, valine and Iysine were higher in TAS, whereas the contents of arginine, glutamic acid, leucine, alanine and valine were higher in TKS. Nucleotides such as IMP and hypoxanthine were principal components in both TAS and TKS. The nitrogen related compounds, TMAO, TMA and total creatinine were determined to be $108.8\;mg\%$ (w/v), $60.5\;mg\%$ (w/v), $62.4\;mg\%$ (w/v) in TAS, and those in TKS were $60.1\;mg\%$ (w/v), $24.1\;mg\%$ (w/v), $67.6\;mg\%$ (w/v), respectively.