• Journal of Food Hygiene and Safety
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• v.19 no.1
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• pp.31-37
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• 2004

This study was performed to investigate the changes of amino nitrogen, total amino acids, free amino acids, and cole. of traditional Korean soybean paste (doen-jang) during the ripening and storage for 12 months. All of the preparation methods for soybean paste followed the recommendations of the Korea Food Research Institute. The components of soybean paste were analyzed at 0, 6, and 12 months. The content of amino nitrogen of soybean paste was significantly higher than that of soybeans or meju (soybean cakes) at the initial stage of storage (p〈0.05), and decreased during the storage. The composition of total and free amino acids and their ratios of soybean paste were changed during the storage. The ratios of free to total amino acids of soybeans, meju, and soybean paste were 0.8%, 17.3%, and 20.4∼32.9%, respectively. Glutamic acid, which represents the savory taste, was detected the most abundantly in soybean paste during the storage. The ratios of free to total amino acids of glutamic acid were 21.1∼41.5% in soybean paste. Lightness, redness and yellowness of Hunter color of soybean paste decreased over time (p〈0.05). The results of this study indicate that the ratios of fee to total amino acids of soybean paste were much higher than those of soybeans, although its contents of total amino acids were much lower than those of soybeans. The results also indicate that this comes from the preparation and fermentation of meju. It was suspected that the organoleptic quality of soybean paste derived from these three components might be inferior over 1 year of storage time.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.6
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• pp.785-790
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• 2011

This study investigated the nutritive quality of olive flounder Paralichthys olivaceus fed either moist pellet (MP) or moist pellet mixed with mushroom extract (MPME) for 6 months. There was no significant difference in crude protein or extractive nitrogen in the muscle of flounder fed MP versus MPME (P > 0.05). The total amino acid content in the muscle of flounder fed MP was $15.22{\pm}5.24$ g/100 g, compared to $19.90{\pm}2.90$ g/100 g for flounder fed MPME. Essential amino acid content was $7.04{\pm}2.21$ g/100 g in the muscle of flounder fed MP versus $8.94{\pm}2.50$ g/100 g for MPME. Total amino acid content was higher in the muscle of olive flounder fed MPME, while essential amino acid content was higher in flounder fed MP. The ratio of non-essential amino acids to essential amino acids was $0.86{\pm}0.07$ for flounder fed MP and $0.81{\pm}0.08$ for flounder fed MPME. There was no significant difference in free amino acid content and fatty acid composition. The breaking strength of muscle of olive flounder fed MP was higher ($1.44{\pm}0.51\;kg/cm^2$) than in flounder fed MPME ($1.29{\pm}0.30\;kg/cm^2$). There was no evidence that dietary additives, such as mushroom extract, increase growth rate or nutritive quality of olive flounder.

• 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.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.6
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• pp.717-724
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• 2013

To characterize the food components of two mussels (wild hard-shelled mussel (HM) Mytilus coruscus, and cultured sea mussel (SM) Mytilus edulis) in Korea, we examined the proximate composition, fatty composition, amino acid/mineral content, texture, collagen content and chemical and taste compounds. Regarding the proximate composition, HM had lower moisture levels and higher crude protein and carbohydrate contents than SM. The amino nitrogen, volatile basic nitrogen and total amino acid contents of HM and SM were 250.6 and 227.3 mg/100 g, 11.2 and 12.0 mg/100 g, and 17,451.1 and 15,334.8 mg/100 g, respectively. The major amino acids were glutamic acid, aspartic acid, glycine, alanine, lysine and arginine. The major fatty acids of HM and SM were 14:0, 16:0, 16:1n-7, 20:5n-3, and 22:6n-3, which did not differ significantly between the two mussels. HM had a higher n-3 polyene ratio, and a lower saturate and monoene ratio than SM. Regarding the taste-active compounds, the free amino acid contents of HM and SM were 1,116.5 and 961.8 mg/100 g, respectively, and the major free amino acids were taurine, glutamic acid, glutamine, glycine, citrulline, lysine and arginine. The primary minerals in both HM and SM were Na, Cl, K and P which did not differ significantly between the two mussels. The soluble and insolube collagen contents of HM and SM were 265.8 and 228.4 mg/100 g, and 119.5 and 121.8 mg/100 g, respectively.

• Food Science and Preservation
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• v.17 no.6
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• pp.820-825
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• 2010

We investigated changes in the quality characteristics of soy sauce made using salts from deep ocean water; such salts are more economic to obtain than sun-dried salt. pH level and buffer action both decreased as fermentation proceeded. The content of the pure extract after 120 d of fermentation was 7.5%(w/w), and increased as fermentation proceeded. Total and amino acid nitrogen levels after 120 d of fermentation were 1.4% and 0.75%, respectively (both w/w). Of the free amino acids (179.8-315.7 mg%), glutamic acid was the most abundant, followed by alanine, lysine, and leucine. The glutamic acid/total free amino acid ratio was 21.0-23.2%. The content of essential amino acids was 78.0-142.3 mg%; this level increased as fermentation progressed.

• The Korean Journal of Food And Nutrition
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• v.30 no.5
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• pp.916-922
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• 2017

This study was conducted to investigate changes in organoleptic properties and taste components including free sugar, organic acid and free amino acid with addition of walnut. Changes in total nitrogen were insignificantly different with addition of walnut. Amino type nitrogen content was decreased in proportion to supplemental level of walnut. Content of organic acids, of which three kinds were detected, such as citric acid, malic acid and lactic acid increased more than two times with addition of walnut. Contents of free sugar and amino acid were decreased with addition of walnut. The proportion of essential amino acid was 40.6~41.4 percent. Glutamic acid in total amino acid was increased in proportion with addition of walnut. The highest sensory evaluation score was recorded in soy sauce with addition of 2 percent walnut. Together, it was expected that 2 percent addition of walnut to soy sauce has a positive effect on the taste of soy sauce.

• Food Science and Preservation
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• v.16 no.1
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• pp.33-39
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• 2009

To evaluate the quality of brown rice vinegar made by traditional fermentation in terms of Zymotechnic data and material content, vinegars prepared using a traditional leavening agent and yeast were compared. Amino acid, total nitrogen, free sugar, organic acid, and mineral levels were assessed, with vinegars made with initial brown rice contents of 12.36% (w/v). Vinegar made using Nuruk as fermenting agent (traditional fermentation, TF), with a brown rice content of 20% (w/v), and vinegar prepared using yeast for fermentation (control fermentation, CF), with a brown rice content of 12% (w/v) were compared. TF vinegar had a total nitrogen content about 2.0.4.6-fold that of CF vinegar. Total nitrogen in TF vinegar was 350.460 mg/100g, and in CF vinegar the level was 100.140 mg/100g. TF vinegar had more minerals, free sugars, and amino acids compared with CF vinegar. When free sugar was assessed, TF vinegar had a glucose level of 3.45 g/100g, double that of CF vinegar. Amino acid levels were five-fold higher in TF vinegar then in CF vinegar. When brown rice content was 36% (w/v), the amino acid level was $6088.22\;{\mu}g/mL$ in TF vinegar and $1194.05\;{\mu}g/mL$ in CF vinegar.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.9
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• pp.1361-1368
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• 2006

Amino acid imbalances refer to the deleterious effects that occur when a second-limiting amino acid or mixture of amino acid lacking a particular limiting amino acid is supplemented in diets marginal in one or more indispensable amino acids. In spite of variation in the conditions that have been used to induce amino acid imbalances, such as protein level in the diet, the extent of difference in total nitrogen content between basal and imbalanced diets, and kinds of amino acids used as imbalancing agents, the conspicuous common features of amino acid imbalances have been a decreased concentration of the limiting amino acid in blood, depression of feed intake and weight gain, and increased dietary content of the limiting amino acid needed to correct the imbalances. There is strong evidence that a decrease in the concentration of a limiting amino acid detected in the anterior prepyriform cortex of the brain is followed by behavioral effects, especially a decrease in feed intake. This might be due to the competition between the limiting amino acid and the amino acids in the imbalancing mixture for transport from blood into brain. One of the biochemical responses of animals fed amino acid imbalanced diets is a rapid decrease in the concentration of the limiting amino acid, which are due in part to an increase in catabolism of the limiting amino acid by the increased activities of enzymes involved in the catabolism of the amino acid. Practically, specific amino acid imbalances could be induced in swine and poultry diets that have been supplemented with lysine, methionine, tryptophan when threonine, isoleucine, valine, etc. are potentially third- or fourth-limiting in diets. In these cases supplementation of the limiting amino acid could be beneficial in preventing the decrease of feed intake that could otherwise occur as a result of amino acid imbalance.

• Korean Journal of Food Science and Technology
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• v.5 no.4
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• pp.210-214
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• 1973

This study analyses and compares the amino acid composition and available lysine content between Korean fermented soybean Meju and its products as well as home-made and commercially made products. The protein quality of the products was evaluated by the result, and the biological value of the proteins was estimated by using the regression equation for chemical score to biological value as calculated by B.O. Eggum. The amino-N content of soybean is found to be 85% of the total nitrogen content and is reduced to approximately 75% in the fermented products except home-made soysauce, where as the content of ammonia-N and other N-compounds is increased. The difference in protein quality between home-made and commercially made products is not found to be significant. The protein quality of soybean is not damaged greatly in the making of Meju but is seriously damaged during the long periods of ripening. After the ripening the chemical score of the products' protein is reduced to approximately one half of the original soybean protein and the available lysine content to $1/3{\sim}1/2$.

• Journal of Nutrition and Health
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• v.13 no.1
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• pp.43-48
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• 1980

In order to identify the taste components of Kochuzang (red pepper paste), glutinous rice Kochuzang were prepared with addition of Saccharomyces rouxii and Torulopsis versatilis respectively. The nitrogen compounds were determined during the fermentation period at intervals and the amino acid components of 210 days aged glutinous rice Kochuzang were measured. Results are as follows; 1) The increment of amino-N and soluble-N of Kochuzang were increased remarkably during fermentation period untill 60 day but after that period, the increment was slowly changed. 2) Ammonia-N of Kochuzang was increased slowly during aging period but after that time, the amount was decreased slightly. 3) Amino-N ratio and Nitrogen solubility of 300 days aged Kochuzang were 23.71-25.38% and 54.12-56.19% respectively. 4) 17 Kinds of amino acid were identified at 210 days aged Kochuzang those were Lysine, Histidine, Arginine, Aspartic acid, Threonine, Serine, Glutamic acid, Proline, Glycine, Alanine, Valine, Methionine, Isoleucine, Leucine, Phenylalanine, Tryptophane and Tyrosine. 5) Total amino acids were 3.5-4.1% which consists of Glutamic acid, 0.95-1.05%, Aspartic acid, 0.63-0.65% and Serine, Proline, Alanine, Valine, Leucine were 0.22-0.28% respectively but Methionine, Histidine and Arginine were below 0.1%, and Tyrosine, Tryptophane and Phenylalanine existed in Kochuzang in small quantities.