• Food Science and Industry
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• v.50 no.3
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• pp.93-104
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• 2017

monosodium L-glutamate (MSG), composed of 88% L-glutamic acid (GLU) and 12% Na, is considered as Generally Recognized as Safe. GLU is accounting for 15% of the total amino acid content in our body. Daily GLU intake is large 3.5-10.6 g from food and 1.3 g from food additive. The daily formed GLU in the body, via degradation of the total protein, is 48-50 g (70 kg of male) and the maintained GLU in the body is total bound GLU (1.4-2.0 kg) and free GLU (10 g). About 88% GLU are consumed at digestive tract, and only 12% GLU enter the blood stream. GLU is generally known to precursors of N-acetyl glutamate and glutamine, substrates for protein synthesis, a neurotransmitter (GABA), and the active site of the enzyme. In addition to protein synthesis, GLU has these key functions within the body, thus this amino acid is critical for healthy body maintenance and function.

• Journal of the Korean Society of Food Science and Nutrition
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• v.14 no.3
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• pp.296-300
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• 1985

This study was carried out to obtain an information for the nutritional value of loach Misgurnus mizolepis, as proximate compositions, contribution of nitrogen, amino acids, three lipid classes and their fatty acid compositions. In total nitrogen contents, protein-N was 81.3% and free amino-N was 15.2%. In amino acid compositions of loach, glutamic acid, lysine, arginine and aspartic acid were the main amino acids in quantity. Total lipids of loach consisted of 57.85% of neutral lipids, 15.95% of glycolipids and 26.20.% of phospholipids. In the neutral lipids, the major fatty acids were palmitic acid, palmitoleic acid and oleic acid. The fatty acid composition in the glycolipids was similar to the pattern in tho neutral lipid, but phospholipids contained higher contents of palmitic acid, oleic acid and arachidonic acid than other lipid classes.

• Korean Journal of Food Science and Technology
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• v.29 no.5
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• pp.913-918
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• 1997

Taste components of traditional kochujang prepared with various raw materials, were investigated during 90 days of fermentation. The major free sugars, maltose and glucose, were higher in malt added kochujang than others. The major organic acids of kochujang were succinic and citric acids, followed by formic acid. The contents of succinic acid in the kochujang decreased during fermentation, whereas that of citric acid increased. Purple sweet potato kochujang was highest in total free amino acids. The major free amino acids were glutamic acid, serine and aspartic acid. They remarkably increased during fermentation. Among the nucleotides and their related components in kochujang, cytidine-5-monophosphate was the most abundant component at the beginning of aging period, while hypoxanthine increased remarkably during fermentation. Kochujang prepared with purple sweet potato Chinese matrimony vine contained higher amounts of organic acids and nucleotides than the others.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.5
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• pp.779-785
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• 1996

The qualities of bread and change of phytic acid during breadmaking with whole wheat flour were investigated. The ratios of ash contents in wheat flour and whole wheat flour were 0.41% and 1.57%, respectively. The ratios of fiber contents in wheat flour and whole wheat flour were 0.14% and 1.83%, respectively. In amino acid analysis, glutamic acid was determined to be 32~36g/100g protein, which was the highest. Lysine, glycine, arginine and aspartic acid were higher in whole wheat flour than those of wheat flour. Proline, glutamic acid, and phenylalanine were higher in wheat flour than those of whole wheat flour. The ratio of phytic acid content in wheat flour and whole wheat flour was 0.312% and 0.734%, respectively. The content of phytic acid during beadmaking was decreased approximately 65% after proofing, while this was almost constant in the process of oven baking. The content of phytic acid in bread with 3% yeast had less hydrolysis than that in bread with 5% yeast during breadmaking. The phytic acid content in the 0.1% yeast food was decreased more than the 0, 0.3, and 0.5% yeast food groups. As the amount of whole wheat flour increased, the volume of bread was decreased, and color became dark. The sensory evaluation was showed the quality of bread to be the highest when the amounts of coarse whole wheat flour and fine whole wheat flour was 20% and 30%, respectively. Though the amount of coarse whole wheat flour and fine whole wheat flour were increased up to 30% and 50%, respectively, external characteristics of bread was remained in normal.

• Korean Journal of Food Science and Technology
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• v.28 no.6
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• pp.1164-1170
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• 1996

Studies were carried out to investigate the changes of constituent components in chestnuts (Castanea crenata Sieb. et Zucc) during storage at $20^{\circ}C$ for 9 weeks and $1^{\circ}C$ for 15 weeks. Ascorbic acid content of chestnut was 4.08 mg% in oxidized form and 17.7 mg% in reduced form which was 81.3% of total ascorbic acid. The reduced form gradually decreased during storage, while the oxidized forms increased during 5 weeks at $20^{\circ}C$ and 7 weeks at $1^{\circ}C$. The major organic acids in chestnut were malic acid, citric acid and quinic acid. Citric acid significantly decreased during storage, while malic acid increased during storage at $20^{\circ}C$ and decreased at $1^{\circ}C$. Free sugars in chestnuts were identified as glucose, fructose, sucrose and maltose. Glucose and fructose decreased after 5 weeks storage at $20^{\circ}C$ followed by an increase thereafter. Sucrose and maltose also increased. The major free amino acids in the chestnut were glutamic acid, aspartic acid, arginine, alanine, proline and serine. Glutamic acid, arginine, alanine, threonine, phenylalanine, valine and lysine increased during storage at $20^{\circ}C$, while proline, serine, isoleucine. leucine and ${\gamma}-aminobutyric$ acid decreased.

• 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.

• Journal of environmental and Sanitary engineering
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• v.2 no.3 s.3
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• pp.13-22
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• 1987

For the amino-N -ratio and N- solubity, irradiated samples were higher than non - irradiated them, that is, 15KGy(l9, 72), 7KGy(l9, 55) of amino-N-ratio were more those of 5KGy(17. 91) and l0KGy(l8, 06). during the fermentation of samples. For the Solubility of nitrogen, irradiated samples were decreased sequencely, such as 10KGy, 7KGy, 15KGy and 5KGy. For the amounts of amino acid, Content of the glutamic acid was the highest in the all samples and the main free amino acids in the Steamed Soybeans Were glutamic acid, proline, arginine, and alanine etc. However the amount of amino acid in the irradiated Sample was notably increased in Comparison with the nonirradiated $(10.8017\%)$ and 7KGy amino acid $(15.4166\%)$ was highest.

• Journal of the Korean Chemical Society
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• v.21 no.3
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• pp.215-218
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• 1977

We have investigated for amino acid composition, molecular weight and terminal amino acid of the main gliadin protein which was purified by Sephadex column. The results were obtained as follows: 1. The highest content of amino acid was glutamic acid for the main gliadin protein. 2. The molecular weight was estimated 60,200 ${\pm}$200 for the main gliadin protein. 3. Identified N-terminal and C-terminal amino acid of the main gliadin protein were phenylalanine and methionine, respectively.

• The Korean Journal of Food And Nutrition
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• v.11 no.2
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• pp.249-255
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• 1998

New drying method was tested comparison with a traditional one used for production of Kwamaegi, semi dry pacific saury in east coast area of Kyungbuk province. During 15 days of total drying period, change in nucleotides and free amino acids were measured in edible portion of pacific saury from different dry methods, natural(traditional) and artificial method. ADP and AMP detected in raw fish were decrease while IMP, inosine, hypoxanthine increased during drying period. K1 values expressed as(Hx+HxR$\times$100/Hx+HxR+IMP) increased gradually throughout drying period, indicating the decline of freshness by drying. Freshness judged by change in nucleotides and related compounds was better in samples from artificial drying than from natural one. Special flavors of Kwamaegi were regarded to be synergistic actions of IMP and some amino acids. Content of total free amino acids of raw fish comprised 2.9g by weight(100g) and sum of glutamic acid, aspartic acid and histidine was over 34% of total amino acid content. Glutamic acid content. Glutamic acid, aspartic acid contents were reduced rapidly from 3rd to 9th day more decrease by artifical drying than by natural drying. Lysine content were gradually increased under two different drying conditions and threonine didn't change by two drying conditions.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.9
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• pp.1114-1121
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• 2017

Bacillus strains not producing harmful components were isolated from Korean traditional soybean products. Extracellular enzyme activities (amylase, protease, cellulase, and xylanase) of isolated Bacillus strains were measured, and Bacillus strains with high protease activity were selected. The selected 15 strains were identified as Bacillus amyloliquefaciens (10), Bacillus methylotrophicus (1), Bacillus velezensis (1), and Bacillus subtilis (3). Among them, B. subtilis JBG17019, B. amyloliquefaciens JBD17076, and B. amyloliquefaciens JBD17109 showed antimicrobial activities against food-borne microorganisms. The production abilities of glutamate, glutamine, and poly-${\gamma}$-glutamic acid (${\gamma}$-PGA) of the selected Bacillus strains were measured to analyze fermentation characteristics related to glutamic acid metabolism. The factor for multivariate was analyzed by the principal components analysis (PCA) method between fermentation characteristics and ${\gamma}$-PGA production. The three principal components were classified according to the PCA method: PC1 [enzyme activity (amylase, cellulase, and xylanase)], PC2 (${\gamma}$-PGA), and PC3 (protease, glutamate, and glutamine). As a result, B. amyloliquefaciens JBD17076 and B. subtilis JBG17019 strains were evaluated as having excellent enzyme activity and ${\gamma}$-PGA production.