• Journal of the Korean Society of Food Science and Nutrition
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• v.7 no.2
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• pp.1-6
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• 1978

Changes of nucleotides and their related compounds during the fermentation of oyster were analyzed by high speed liquid chromatography. In raw oyster, dominant 5'-UMP was $26.1{\mu}mole/g$ and the content of uracil, hypoxanthine, 5'-GMP were 5.2, 3.8, 2.8 and $2.7{\mu}mole/g$ on moisture and salt free base, respectively. The content of cytosine, 2',3'-CMP, 5'-AMP and 2',3'-GMP were lower than $1.0{\mu}mole/g$ and guanine were detected in trace amount. 5'-UMP, uracil, hypoxanthine, 5'-IMP and 5'-GMP were abundant in both raw sample and fermented products. 5'-UMP and 5'-IMP were decreased slowly while 5'-AMP, 2'3'-CMP, cytosine and guanine were increased during the fermentation, and the increase of 5'-GMP and uracil were fluctuated. The content of hypoxanthine in raw oyster was increased to 3.1, 4.2 and 7.7 times of raw sample after 19, 36 and 68 days of fermentation, respectively.

• Applied Biological Chemistry
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• v.23 no.2
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• pp.89-105
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• 1980

Soysauce was made in the salt concentrations of 22.0% and 28.5%, and the changing aspects in nucleotides and their related compounds, free amino acids, free sugars and non-volatile amines which are related to the taste components during the fermentation process with a view to examining the taste components in the ordinary Korean soysauce were studied. And then artificial soysauce was prepared by applying the values derived from the analysis and measurement, and its sensory evaluation was performed. As the result of the sensory evaluation of artificial soysauce prepared according to the value of components analyzed from soysauce which had been fermented for fourty days in the salt concentration of 22.0%, it has been found that artificial soysauce was similar in taste to ordinary Korean soysauce. So, the following facts have been found: glutamic acid and aspartic acid have MSG-like taste, and IMP has a synergistic effect with these acids, which play great roles in ordinary Korean soysauce; both free sugars such as galactose and amino acids such as glycine, alanine and lysine have sweet taste; both amines such as tyramine and histamine, and amino acids such as valine, leucine, isoleucine, and phenylalanine have bitter taste; these components, combined with saline taste of salt and sour taste of organic acids, are assumed to form the unique taste in the ordinary Korean soysauce.

• Korean Journal of Food Science and Technology
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• v.15 no.1
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• pp.1-5
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• 1983

Large quantities of an ascidian, Styela plicata, are harvested annually as the by-product of oyster culture on the south coastal area in Korea. It has been traditionally favored and consumed because of its peculiar taste and flavor. But no study on its taste compounds has been reported. An investigation on the taste compounds of fresh meat and integument of an ascidian has been carried out by a series of analysis of taste compounds including nucleotides, free amino acids, betaine, TMAO, TMA and total creatinine. The most abundant nucleotides in fresh meat were AMP and IMP. Their contents were $1.2\;and\;0.8{\mu}mole/g$, respectively. The contents of nucleotides and their related compounds in integument show similar tendency as in fresh meat but their quantities were very low as compared with those in fresh meat. Seventy two percentage of the total free amino acids in fresh meat was consisted of proline, alanine, glutamic acid, glycine and serine. They occupied also 82% of the total free amino acids in integument, but the amount of free amino acids in integument was about 1/10 of that in fresh meat. The contents of betaine-N and creatinine-N were 6.1 and 2.1% of the extractive-N in fresh meat, respectively. The amounts of TMAO-N and TMA-N were very low contents in fresh meat and trace in integument.

• Fisheries and Aquatic Sciences
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• v.4 no.4
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• pp.246-251
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• 2001

As a series of studies on improving quality of seasoned-dried Pacific saury, fatty acid compositions and taste compounds of the seasoned-dried saury treated with liquid smoke (T2 product) were examined during storage, comparing with control (C, seasoning only). In the both samples, the major fatty acids were 22:6n-3, 16:0, 22: In-11I, 20: In-11, 18: In-9, 14:0, 20:5 n-3 and 16:1n-7. The contents of saturated fatty acids in C and T2 increased with increasing storage period, while those of polyunsaturated fatty acids decreased. After drying, the contents of 7 non-volatile organic acids contents detected in this study decreased, and the others of non-volatile organic acids, except for malic and citric acids, in both C and T2 decreased with storage period. The contents of nucleotides and their related compounds in both C and T2 decreased with increasing storage period. The content of total free amino acids in raw sample was 556.96 mg/100g and increased up to 895.77 mg/l00 g and 958.40 mg/100g in C and T2, respectively, after drying, and total contents of free amino acids in both C and T2 somewhat decreased after 60 days of storage.

• Journal of Nutrition and Health
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• v.11 no.3
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• pp.13-20
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• 1978

Changes of free amino acids, nucleotides and their related compounds as taste compounds during sun drying of ascidian Cynthia roretzi, were analyzed by amino acid autoanalyzer and high speed liquid chromatography. In fresh ascidian, the results showed that 5'-UMP $(12.1\;{\mu}mole/g)$ was dominant and the content of cytosine, 2', 3'-CMP, 2', 3'-GMP, hypoxanhtine, 5'-AMP,5'-IMP were 5.8, 3.4, 3.1, 2,3, 1.7 and $1.3\;{\mu}mole/g$ ondry base respectively. 5'-IMP, 2', 3'-CMP and 2', 3'-GMP tended to degrade slowly and 5'-AMP, cytosine and 5'-UMP were decreased rapidly while hypoxanthine were increased remarkably during the sun drying. In dried ascidian, the content of hypoxanthine was the highest, 7.2 mole/g on dry base, whereas that of 5'-AMP $(0.5\;{\mu}mole/g)$) and 5'-IMP $(0.9\;{\mu}mole/g)$ were lower. Glutamic acid, alanine and serine were dominant amino acid in the fresh extracts, having 22.4% (611.3mg%, on dry qase), 19.8% (540.5mg%) and 14.8% (402.8mg%) of the total amino acid content respectively. The content of tyrosine, histidine, lysine, methionine, isoleucine and valine were low, and proline, phenylalanine were detected in trace amount. The free amino acid were not changed in composition but the increase of total free amino acid was approximately 116.8mg% during sun drying. In sun dried ascidian, glutamic acid (691.0mg, on dry base), alanine (641.3mg%), serine (469.5mg%), threonine (234.8mg%) and glycine (206.3mg%) were dominant amino acid. It is believed that glutamic acid, serine, alanine, threonine, glycine and hypoxanthine play an important role as taste compounds in sun dried ascidian.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.13 no.3
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• pp.115-119
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• 1980

Snakehead, Channa argus, is one of the most palatable fresh-water fishes in Korea; however, relatively little is known about the characteristics of taste. The present study was undertaken to analyze the proximate composition as well as the taste compounds of dorsal muscle of Korean snakehead. In the dorsal meat, glycine, taurine, alanine and lysine were abundant. Among these, glycine was the most dominant, occupying $63\%$ of total free amino acid. The amount of IMP was $2.78{\mu}mole/g$ and those of another nucleotides and their related compounds were not so high as compared to that of IMP. About $43\%$ of the total extractive-N was total creatinine-N. But the content of betaine-N was very low, occupying only $0.8\%$ of the total extractive-N and TMA-N and TMAO-N were trace in content. In snakehead, the sum of the nitrogen in these constituents amounted to nearly $80\%$ of total extractive nitrogen.

• Korean Journal of Food Science and Technology
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• v.22 no.2
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• pp.221-226
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• 1990

Fish flesh of Alaska pollack containing 5% of corn starch were fermented with 8 strains of mold and monitoring of their flavor characteristics, acceptability, nucleotides and their related compounds, amino acid compositions were conducted. All strains were grown vigorously on fish flesh media and formed their characteristic spores with unique flavor by strains. Amino type nitrogen $(NH_2-N)$ content of fermented fish flesh (FFF) were 25-26 times higher than that of raw flesh and 6-15 times higher in extractable nitrogen (Ex-N) content . The strains which produce more ADP (Adenosine 5'-diphosphate) in FFF also showed much higher level of IMP (Inosine 5'-monophosphate) and GMP (Guanosine 5'-monophosphate) content than that of raw flesh. Amino acid composition were differ by strain but lysine was generally highest and arginine, glutamic acid, leucine and alanine in order In review of sensory evaluation , total content of nucleotides, $NH_2-N$, Ex-N and amino acid compositions, suitable strains for fish flesh fermentation were Aspergillus oryzae KFCC 11371, Asp. oryzae KFCC 32343, Penicillium roqueforti KFCC 11269 and Asp. quercinus.

• Korean Journal of Food Science and Technology
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• v.29 no.2
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• pp.230-239
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• 1997

In order to investigate the composition and the actual condition of extractive nitrogenous constituents in Tohajeot (a salted and fermented freshwater shrimp, Caridina denticulata denticulata) and in seasoned Tohajeot which were sold in the markets, the extract was analyzed separately into extractive nitrogen, free amino acids, oligopeptides, nucleotides and related compounds, quaternary ammonium bases, and guanidino compounds, using specimens collected at the fish markets of Yosu and Naju cities in 1994 and 1995. The salinity of Tohajeot was very high $(23.6{\sim}25.1)%$, but seasoned Tohajeot was relatively low $(8.4{\sim}11.4%)$. The extractive nitrogen in the extracts of Tohajeot and seasoned Tohajeot was $311{\sim}531\;mg\;and\;256{\sim}429\;mg$, and the total of free amino acids in them were $1,159{\sim}2,584\;mg\;and\;1,012{\sim}1,672\;mg$ respectively. Glutamic acid, leucine, lysine, histidine, alanine, ornithine, and tyrosine were the major amino acids in Tohajeot extract, and glutamic acid, lysine, arginine, aspartic acid, histidine, leucine and alanine were the main amino acids in seasoned Tohajeot. As for nucleotides and related compounds in them were $2.64{\sim}4.82\;{\mu}mol\;and\;1.08{\sim}1.93\;{\mu}mol$ respectively. Homarine, trigonelline, glycinebetaine and ${\beta}-alaninebetaine$ were detected in them. Homarine was the most abundant, ranging from 18 mg to 86 mg, but the others were very low. The content of major nitrogenous constituents in Tohajeot extract, such as extractive nitrogen, free amino acids, oligopeptides, nucleotides and related compounds, and betaines, was more abundant than that in seasoned Tohajeot extract. But the nitrogenous constituents of Tohajeot extract were poorer than those of anchovy sauce which was sold in the markets. Possibly, the extractive nitrogenous components, which consisted of total betains, total free amino acids, and phenylalanine might be recommended as the quality indices of standardizing Tohajeot and seasoned Tohajeot.

• The Korean Journal of Food And Nutrition
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• v.11 no.4
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• pp.437-443
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• 1998

This research is to establish the basic data of the nutritive value and improve our diet. In the part of the leaf and stem of the wild and cultivated horned rampion (Phyteuma japonicum Mig), the components such as chemical compositon, vitamin C, free sugar, mineral, nucleotide and its related compounds, composition and free amino acid were analyzed one after another. Content of the crude lipids and proteins was determined much higher in its wildness than in its cultivated horned rampion; while, that of carbohydrates was higher in the former than in the latter. The content of vitamin C was retained higher in the leaf than in the stem horned rampion. And the content of calcium among the detected minerals was outstanding in all of the samples collected, and potassium and magnesium was the next ones in its order. The main components of free sugars in both the wild and cultivated horned rampion were glucose and fructose, and their content was higher in the stem than in the leaf. Nucleotide and its related compounds were identified with 5 kinds of nucieotides such as CMP, UMP, IMP, AMP and hypoxanthine (Hx), and the content of Hx and AMP was the highest I the wild and cultivated samples, respectively. In the composition amino acid of the wild horned rampion, glutamic acid, aspartic acid and phenylalanine was outstandingly abundant; while, such amino acid as methinone and proline was small and besides cysteine couldn't be detected in the stem. Total amounts of composition amino acid in the leaf was 2118.0 and 1120.1mg% in the wild and cultivated sample, respectively. In the free amino acid of horned rampion, the total amount ranged from 8.5 to 50.1mg.%, which were lower level than that of composition amino acid. But the number of free amino acid was 29 kinds, which was bigger in its number than that of composition amino acid detected 17 kinds.

• The Korean Journal of Food And Nutrition
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• v.9 no.4
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• pp.398-403
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• 1996

To produce low salt fermented anchovy by an accelerated method with Asp. oryzae and Bacillus sp. koji and taste properties after the 60 day fermentation were examined. The main free amino acids of 60 day fermented anchovy paste were valine, isoleucine, proline, alanine, lysine, glutamic acid and aspartic acid. Total amount of free amino acids was the highest in non koji anchovy paste wit 2,624.76mg%. Among the koji added samples, Asp. oryzae koji added on was the highest in the amount o free amino acids. Hypoxanthine accounted for 84.14~95.4% of total nucleotides and their related compounds; Asp. oryzae koji added anchovy paste was the highest in nucleotides other related. Citric acid and lactic acid accounted for 94.9~96.7% of total non-volatile organic acids; Asp. oryzae koji added sample was the highest in non-volatile organic acids with 287.93mg%. The Hunter a and b values gradually increased during the fermentation, but the L value decreased until day 30 or 40 and increased steadily after that. The a and b values were higher in the use of Asp. oryzae koji than in Bccillus sp. koji, but the L value was to the contrary. The Asp. oryzae koji added anchovy paste was good in the aspect of color and taste compared to others. In the aspect of odor, the anchovy paste using the mixture of Asp. oryzae and Bacillus sp. koji was the best. Overall aceptability of sensory evaluation was higher in the mixture of Asp. oryzae and Bacillus sp. koji tan in the others.