• Korean journal of food and cookery science
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• v.17 no.5
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• pp.517-522
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• 2001

Changes of nucleotides and their related compounds in raw, cooked and frozen fish muscle were studied with HPLC. Red sea bream(cultured and wild) and flounder(cultured, cultured with Obosan(equation omitted) and wild) were used for this study. In nucleotides, contents of ATP was similar to that of IMP and some of H$\times$R(inosine) and H$\times$(hypoxanthine) were existed in fresh muscle. ATP was decomposed rapidly and contents of IMP became different between cultured and wild fish after 6 hours. The content of IMP was lower in the cultured red sea bream(3.39$\mu$ mole/g) and flounder(3.17$\mu$ mole/g) than in the wi1d red sea bream(7.31$\mu$ mole/g) and flounder(5.03$\mu$ mole/g). But, the flounder cultured with Obosan contained the largest amounts of IMP After 24 hours, K values of cultured fish muscle(27.7%, 28.2%) were higher than that of wild ones(22.8%, 24.3%). The K value of cultured flounder fed with 0.3% Obosan(equation omitted)(25.7%) was between cultured and wild flounder. IMP was the one which existed the most in cooked and frozen muscle. Amounts of H$\times$R and H$\times$ were more in cooked and frozen muscle. than in raw muscle. From these results, we could suggest that the wild one was more palatable and fresher than the cultured one and the palatability of cultured one seemed to be improved depanding on the feed.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.11 no.2
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• pp.65-83
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• 1978

This study was attempted to evaluate the taste of broiled-dried sea mussel which is a traditional dried Sea food in Korea. The contents of such compounds as free amino acids, nucleotides and their related compounds, TMAO, betaine, and nonvolatile organic acids were analysed. From the results of analysis of nucleotides, the contents of AMP and ADP in broiled-dried Mytilus coruscus and Mytilus edulis appeared higher than other nucleotides and tended to increase slightly after cooking, drying, and storage which might be due to both their stability and the addition of degradation of nucleic acids during cooking. In the free amino acid composition of fresh samples abundant amino were taurine, glycine, serine, glutamic acid, alanine, arginine, threonine, tyrosine, lysine and valine in order. Such amino acids as histidine, leucine, methionine and isoleucine were poor and both proline and phenylalanine were merely trace. The free amino acid composition in the extract of Mytilus corucus and Mytilus edulis after broil-drying was not changed. These amino acids, taurine, glycine, feline, glutamic acid, alanine and arginine were abundant in dried samples as well as in the fresh. The total free amino acid was greatly reduced after cooking and drying ranging from $76.3\%$ to $79.7\%$ loss to that of tile fresh. The content of betaine shelved the same tendency as in total free amino acid while TMA slightly increased relating to TMAO decrease during broil-frying. Such nonvolatile organic acids as succinic, lactic, malic and fumaric acid were abundant in both fresh and broiled-dried samples whereas oxalic and pyruvic acid were poor. It is found that the taste compounds of broiled-dried Mytilus coruscus and Mytilus edulis were composed of amino acids as glycine, serine, alanine, glutamic acid, arginine, and betaine, TMAO, ADP, AMP, and organic acids such as succinic acid, lactic acid, malic acid and fumaric acid. No significant differences in the taste compounds between male and female as well as between Mytilus coruscus and Mytilus edulis was not observed.

• Korean journal of food and cookery science
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• v.16 no.2
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• pp.173-181
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• 2000

To understand the influences of NaCl concentration and fermentation temperature on the ripening process of low salt fermented squids, squid with 5%, 7% and 9% salt were fermented at 10$\^{C}$ and 20$\^{C}$. The result of the changes of volatile basic nitrogen and free amino acids during the fermentation of squids are as follows. As a result of the observations on the changes of physicochemical components during the fermentation process of the low-salted squids, all the pH, VBN and NH$_2$-N were increased and therefore the fermentation was promoted. Considering the changes of net components according to the fermentation, ATP (Adenosine triphosphate) and ADP (Adenosine diphosphate) lost and could not be detected among the nucleotides and their related compounds. Besides, AMP (Adenosine monophosphate) existed only in the initial stage and inosine, hypoxanthine were the main components of nucleotides and their related compounds. Nonvolatile organic acids are mainly lactic acid, acetic acid and also they occupied more than 80%. Seeing the composition of free amino acid, the major amino acids are proline, arginine, methionine, alanine and glutamic acid.

• Journal of Nutrition and Health
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• v.17 no.3
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• pp.169-177
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• 1984

The changes in nuclecotides and their related compounds during the fermentation of Clam, Tapes japonica, were analyzed by high speed liquid chromatography. In raw Clam, dominant ADP was $7.86\;{\mu}mole/g$ on moisture and salt free base and the content of ATP was $3.85\;{\mu}mole/g$, AMP $3.71\;{\mu}mole/g$, hypoxanthine $0.28\;{\mu}mole/g$, inosine $0.15\;{\mu}mole/g$, respectively. But IMP was not detected in Clam ADP, ATP and AMP decreased while inosine and hypoxanthine incraesed by twenty two times and thirty there times respectively, after 63 days fermentation, when compared with raw samples. TMA- N increased while TMAO - N decreased during the fermentation The amount of TMAO nitrogen in 63 days fermented Clam was 66.0mg% on moisture and salt free base. It was belived that inosine, hypoxanthine and TMAO play an important role as flavour compounds in fermented Clam.

• Korean Journal of Food Science and Technology
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• v.31 no.1
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• pp.13-19
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• 1999

In order to investigate the composition and the actual status of extractive nitrogenous compounds in the fresh 'Gae-bul' (echiuroid), a kind of echiurida (Urechis unicinctus), the extract was analyzed separately into extractive nitrogen, free amino acids (FAAs), oligopeptides, nucleotides and related compounds, quaternary ammonium bases, and guanidino compounds, using specimens collected at fish market in April 1988. The extractive nitrogen of echiuroid was $601{\sim}610mg/100g$. Thirty-two kinds of FAAs were found, and the total of them in it was $2,437{\sim}2,609\;mg$. Glycine, alanine, taurine, and serine were the major FAAs in the echiuroid extracts. The large amount of glycine $(1,075{\sim}1,171mg)$ was noted in the extract. The sum of ATP and its related compounds was $3.04{\sim}3.12\;{\mu}mol/g$, and predominant compound was the AMP. Besides, CTP, GTP, UTP and their related compounds were also detected, and the total amount of them was $1.92{\sim}3.74\;{\mu}mol/g$. The lower homarine, trigonelline, TMAO, TMA, and creatine were detected in the extracts. The extractive nitrogenous constituents of medium size and large size echiuroid were almost the same level each other. The total nitrogens of the compounds analyzed for each samples accounted for more than 90% of the extractive nitrogen in this study.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.15 no.2
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• pp.117-122
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• 1982

Abalone, Haliotis diversicolor japonica, is one of the most palatable sea foods in Jeju-Do, Korea : however relatively little is known about the characteristics of its taste. This study was undertaken to establish the basic data for evaluating the taste compounds in the extract of abalone including nucleotides and their related compounds, free amino acids, trimethylamine oxide, trimethylamine and total creatinine. The amount of AMP was $2.21{\mu}mole/g$ while IMP and inosine was trace in content. In the extracts, taurine, arginine and glycine were abundant holding $39.9\%,\;25.4\%,\;14.0\%$ of total free amino acids content respectively, but tyrosine and phenylalanine was trace in content. TMAO, TMA and total creatinine were poor in content marking $5.4mg\%,\;1.0mg\%\;and\;5.0mg\%$. It was presumed that the characteristic flavor of abalone was mainely attributed to free amino acids. Organic acids, nucleotides and their related compounds played auxiliary role in the characteristic flavor of abalone.

• Korean Journal of Food Science and Technology
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• v.4 no.4
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• pp.317-321
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• 1972

Octopus Octopus vulgaris was dried with open air at $17{\sim}20^{\circ}C$ for 90 hours. Nucleotides and related substances were collected by extraction with cold perchloric acid, and their amounts were determined by ion exchange column chromatography. The contents of inosine, hypoxanthine and ADP in raw sample were 9.4, 5.1 and 4.1 ${\mu}mole/g{\cdot}dry\;wt.$ respectively. ATP and AMP were very low in content. But IMP was not detected in Octopus muscle. ATP, ADP and inosine tended to degrade rapidly during sun drying while AMP and hypoxanthine were increased. Especially, hypoxanthine were increased about three times during sun drying and also it was increased about two times during three months storage after sun drying.

• 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 Food Science and Technology
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• v.17 no.4
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• pp.283-288
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• 1985

Fermented big eyed herring. Harengula zunasi, and slimy, Leiognathus nuchalis, were widely used and contributed in diet of people in southern coast of Korea. In this paper, in order to elucidate the taste compounds of fermented big eyed herring and slimy, the nucleotides and their related compounds, free amino acids, TMAO, betaine, total creatinine, and minerals were analyzed. In fermented big eyed herring, lysine, alanine, leucine, isoleucine and valine were dominant holding 88.6% of the total free amino acids while alanine, leucine, isoleucine and lysine in fermented slimy were dominant holding 84.4% of total free amino acids. In the nulceotide and their related compounds, hypoxanthine was the major component in both samples. The contents of betaine, TMA and total creatinine were 99.7mg%, 24.2mg% and 432.8mg% in fermented big eyed herring, 107.6mg%, 19.5mg% and 258.8mg% in fermented slimy, while the contents of TMAO appeared trace in both samples. In the minerals of both samples Na and Ca were dominant holding 37,471-45,100.8ppm, 14,117.1-19,948.1ppm, respectively. From the omission test and chemical analysis, it is concluded that the major taste compounds of fermented big eyed herring and slimy were amino acids such as alanine, lysine, leucine and isoleucine. Minerals, nucleotides and their related compounds, betaine and total creatinine acted as an auxiliary role in taste of both fermented samples.

• Food Science of Animal Resources
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• v.40 no.6
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• pp.908-923
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• 2020

The objective of this study was to compare tastes-related components and eating quality properties between Hanwoo steer and cow meats. Longissimus thoracis (LT) muscles with same quality grade (1⁺ grade) collected from left sides of the steer and cow carcasses were used for analyses of technological quality traits, free amino acids (FAAs), metabolites, nucleotides, fatty acids and sensory attributes. there were no differences occurring in the chemical composition (fat, protein, moisture and collagen) and technological quality traits (cooking loss, water holding capacity, shear force and color) between the two beef types (p>0.05). The cow meat exhibited significantly higher amounts of some FAAs associated with umami (e.g., glutamic acid and lysine), sweetness (e.g., proline and glutamic acid) and saltiness (e.g., histidine and glutamic acid) compared to the steer meat (p<0.05). Regarding the nucleotides, no differences occurred in all the identified nucleotides between the two beef types (p>0.05). A total of 27 metabolites were identified, however, only some compounds (e.g., acetate, creatine, creatinine, glucose and inosine, etc.) showed their significantly higher amounts in the cow meat compared with those in the steer meat (p<0.05). In terms of sensory aspects, the panelists found no differences in scores of all the eating quality traits between the two sex types of beef (p>0.05). Overall, excepts some variations in tastes-active compounds, there were no differences in the quality characteristics in general and eating quality in particular between the cow and steer meats when they were in the same quality grade.