• 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.

• Fisheries and Aquatic Sciences
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• v.2 no.2
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• pp.135-141
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• 1999

In order to investigate the composition of extractive nitrogenous components in the diploid and the triploid oysters, Crassostrea gigas, cultured at the south coast of Korea, the whole edible part (whole body) was analyzed into extractive nitrogen, free amino acids, oligopeptides, ATP and its related compounds, quaternary ammonium bases, and guanidino compounds using specimens collected from April to May of 1992. The major free amino acids in the diploid and the triploid were taurine, proline, alanine, glycine, glutamic acid hypotaurine, glutamine, arginine, aspartic acid, and $\beta-alanine$. There was no conspicuous difference in the constituents of free amino acids between the diploid and the triploid. A lot of hypotaurine was detected in the diploid and the triploid of oyster and the contents of them were 107 mg and 123 mg/100g, respectively. The compounds, glycinebetaine, homarine and trigonelline were found in both the diploid and the triploid. Among them, glycinebetaine was the most prominent in all the samples. The amount of protein, glycogen, extractive nitrogen, oligopeptides, ATP and its related compounds, and free amino acids in the triploid was higher than that of the diploid (p<0.10)

• Journal of the Korean Society of Food Culture
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• v.12 no.4
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• pp.383-389
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• 1997

This study was carried out in order to analyze the changes in nitrogen containing taste compounds of traditional Korean soy sauce with varying Meju concentrations (Meju-water ratios of 1:4 and 1.3:4) and ripening periods (up to 2 years), and to investigate correlation between sensory characteristics and taste compound contents via contents assay and sensory evaluation of soy sauce samples. Nitrogen compound contents were higher in 1.3:4 than in 1:4 for all nitrogen compounds. Free amino acid contents were highest in soy sauce ripened for 210 days. Among amino acids, glutamic acid was highest concentration. Nucleotides and their related compound contents did not vary with concentrations and were highest in the sample ripened for 210 days. In direct sensory evaluation of soy sauce, overall taste preference showed positive correlation to sweet taste. Likewise, overall taste preference showed positive correlation to umami, nutty, sweet taste in the sensory evaluation of seaweed soup seasoned with soy sauce. Sensory evaluation score was higher in 1.3:4 than in 1:4. According to the correlation assay of taste compound contents and sensory evaluations, nitrogen compounds (such as amino type nitrogen), amino acids (such as glutamic acid, aspartic acid, and lysine, and etc.), nucleotides (such as AMP, IMP, and etc) had significant influence on the sensory characteristics of soy sauce, and therefore we can conclude that these compounds affect the taste and quality of soy sauce.

• Applied Biological Chemistry
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• v.8
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• pp.11-20
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• 1967

In order to study the change of nitrogeneous compounds during the "Natto" preparation, the contents of insoluble protein, water soluble protein and amino nitrogen were determined and the pattern of peptides and amino acids was investigated by paper chromatography for the fractions resulting from molecular sieving. The results are summarized as follows: 1. Insoluble protein nitrogen which was increased to 84% by autoclaving the native soybean decreased to 44%, whereas the trichloroacetic acid soluble nitrogen increased from 8% to 45% during Natto preparation, But the soluble protein nitrogen showed a slight increase. 2. Fractionation of the peptides using Dowex-50 resins showed that they consisted mostly of lower molecular weight peptides which increased in accordance with the progress of fermentation, especially after 30-hour period. 3. Sixteen known and two unknown amino acids, and three peptides with different Rf values were identified during the Natto preparation. Their appearance showed some difference in that phenylalanine appeared after 10 hours, methionine, after 20 hours and proline, after 30 hours, respectively. The three peptides appeared at the different stage of fermentation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.4
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• pp.680-685
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• 1994

Total nitrogen content, proline, free amino acids, sugars, invertase and diastase activities in native bee-honey (NBH) and foregin bee-honey (FBH) harvested from our different areas of Kangwon , Korea were determined. The total nitrogen contents of NBH and FBH were 0.077$\pm$0.033mg% and 0.055$\pm$0.022mg%, respectively. Proline content in NBH was 42$\pm$10mg% and waqs found to be much lower than that in FHB. Phenylalanine and proline were major free amino acids both in NBH and FBH . The content of total free amino acid in FBH were twice as much as that in NBH , however isomaltose content in NBH were almost two times more than that in FBH. Other sugars including fructose, glucos , sucrose and maltose were also analyzed. No differences were found between NBH and FBH in invertase activities, but comparing to these of FBH ,lower values of diastase activity in NBH were observed.

• Asian-Australasian Journal of Animal Sciences
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• v.3 no.3
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• pp.165-175
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• 1990

This experiment was conducted to examine the effects of different carbohydrate and nitrogen source upon the utilization of amino acids in the small intestine of sheep. The results obtained are as follows: 1) For the quantities of total amino acid-N(TAA-N), essential amino acid-N(EAA-N) and nonessential amino acid-N(NEAA-N) passing at the duodenum and ileum except NEAA-N passing at the ileum were no significant differences (p>0.05) between diets. The quantities of NEAA-N passing at the ileum for the diets containing meat and bone meal were significantly higher (p>0.05) than the diets containing soybean meal. The mean values for the proportionate disappearance apparently digested TAA-N, EAA-N and NEAA-N within the small intestine for four diets were $0.692{\pm}0.0449$, $0.702{\pm}0.0132$ and $0.682{\pm}0.726$, respectively. 2) There were no significant differences (p>0.05) in duodenal individual amino acid flow between diets with the exception of aspartic acid and glycine. The amounts of each amino acid in duodenal digesta, expressed as a proportion of the amounts ingested for the four diets, were shown that there were net gains of EAA with the exception of arginine and NEAA with the exception of glutamic acid, glycine and praline prior to the small intestine. 3) Within the small intestine, there were no significant losses of each EAA (p>0.05) but significant losses of aspartic acid and glycine of NEAA between diets (p<0.01). The mean values of the proportionate losses of methionine, alanine and lysine within the small intestine were $0.816{\pm}0.04$, $0.767{\pm}0.04$ and $0.732{\pm}0.01$, respectively.

• The Korean Journal of Food And Nutrition
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• v.14 no.2
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• pp.167-174
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• 2001

Soy sauce was prepared with the addition of Gorosoe and bamboos sap instead of tap water to make ordinary soy sauce, respectively. The changes of such compounds during fermentation as minerals, free sugars, organic acids and free amino acids were analyzed. Total mineral contents in the 90 days fermented soy sauce from Gorosoe and bamboos sap were increased by 2.0 and 4.4 times as compared with those of control samples, respectively. Especially the increase of calcium, potassium and magnesium in soy sauce of sapes were derived from those of saps. The sugars were found to be only glucose and galactose in control samples, but they were detected not only above sugar but also fructose and sucrose in soy sauce of saps. Butyric acid in detected organic acid were dominant in all stray sauce samples. In the free amino acid composition of control samples, leucine, phenylalanine, isoleucine, lysine and glutamic acid were abundant amino acids. Amino acid such as isoleucine, leucine and phenylalanine were decreased, the rest 11 kinds of amino acids containing phosphoserine were increased during the fermentation of control samples. Increasing and decreasing patterns of free amino acids during fermentation of sap soy sauce were similar to control samples. Total nitrogen, amino acid nitrogen and ammonia nitrogen were increased during their fermentation.

• Journal of the East Asian Society of Dietary Life
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• v.11 no.4
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• pp.281-288
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• 2001

The autoclave method and the traditional cooking method were compared for nutrients(especially, minerals), color difference, viscosity, reduction of sugar and amino nitrogen content of brown stock. The autoclave cooking method is better than the traditional cooking method for retaining protein and amino nitrogen contents, as well as for reducing sugar content. Also, reducing sugar content increased by the autoclave cooking method. Since the color of brown sauce was related with the reducing sugar content, the autoclave cooking method was more effective than the traditional cooking method for the color development of brown stock. Since the autoclave method can reduce the cooking time without a loss of quality in brown stock, the autoclave method is a viable alternative to the traditional method of preparing brown stock.

• Korean Journal of Microbiology
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• v.1 no.1
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• pp.19-25
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• 1963

The studies could be summarized as follows: 1. Standard Rf Values were made as Table II for the identification of amino acids. 2. Amounts of free amino nitrogen in eggs were increased about 0.03% (Table IV) while the amounts of total nitrogen (Table III) were increased lower percentage during the ten days of development. 3. Three unknown substances were found newly during the development. 4. Eight ninhydrine positive amino acids were present, in the fresh embryonic eggs, but the numbers increased to eighteen after fifty days of development. 5. Through the development, there were large amounts of glutamic acid, aspartic acid and alanine. 6. After fifty days development, the amount of amides, such as asparagine, glutamine and alanine were increased very large which were very small amount before it and the amount of asparagine were more than that of glutamine. 7. Tryptophane, Cystine , Histidine were detected after 50 days of development. This is very remarkable fact.

• Proceedings of the Korea Hospitality Industry Research Society Conference
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• 2003.05a
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• pp.51-58
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• 2003

The autoclave method and the traditional cooking method are compared for nutrients, mineral, color difference, viscosity, reducing sugar and amino nitrogen content of brown stock. For protein and amino nitrogen contents, the autoclave cooking method is better than the traditional cooking method. Also, reducing sugar content is increased by the autoclave cooking method. Since the color of brown sauce is related with reducing sugar content, the autoclave cooking method is more effective than the traditional cooking method for the color of brown sauce. Since the autoclave method can reduce the cooking time without the loss of quality in brown stock, the traditional method can be substituted by this new method.