• Korean Journal of Food Science and Technology
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• v.26 no.5
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• pp.561-566
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• 1994

The kinds of kochujang were discriminated by using their organic acid compositions, GC peak areas of volatile concentrates and flavor intensity determined by sensory evaluation. Tested kochujang were 51 kinds of traditional kochujang and 10 kinds of industry-produced kochujang in the market. The traditional kochujang included 20 kinds of Sunchang kochujang prepared with glutinous rice, 11 kinds of Boeun kochujang prepared with barley and 20 kinds of Sachun kochujang prepared with wheat. Boeun kochujang was distinguished from other kinds of traditional and industry-produced kochujang by using canonical discriminant analysis for the compositions of organic acids. Among organic acids, lactic acid was the most contributing variable for the discrimination of various kochujang. Traditional and industry-produced kochujang could be classified into 4 groups by using discriminant analysis for GC peak areas. The peak number 2, 4, 8 and 11 were found to be highly contributing variables for the discrimination of kochujang by using stepwise discriminant analysis. Industry-produced kochujang was discriminated from traditional kochujang by using canonical discriminant analysis for the intensity of 8 kinds of flavor property. The taste 'umami' was found to be the most contributing variable for the discrimination of kochujang.

• Korean Journal of Food Science and Technology
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• v.26 no.1
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• pp.12-17
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• 1994

Physicochemical characteristics of traditional kochujang fermented for 6 months and commercial kochujang were compared. Tested kochujang included 18 kinds of Sunchang kochujang prepared with glutinous rice, 10 kinds of Boeun kochujang prepared with barley and 17 kinds of Sachun kochujang prepared with wheat, and 10 kinds of commercial kochujang. Major free sugar was found to be glucose both in traditional and commercial kochujang. Fructose, maltose, and sucrose were also detected in small amounts. The contents of free sugars in traditional kochujang was approximately one fourth of those presented in commercial kochujang. Commercial kochujang showed the highest level of total free amino acids followed in decreasing order by Sachun, Sunchang, and Boeun kochujang. The most abundant free amino acid was serine in Sunchang kochujang and aspartic acid both in Boeun and Sachun kochujang. On the other hand, glutamic acid was the most abundant amino acid in commercial kochujang. Volatile organic acids in various kochujang were determined and acetic, propionic, butyric, and 3-methyl butanoic acids were found in traditional kochujang. However, 3-methyl butanoic arid was not found in commercial kochujang. The most abundant volatile acid was acetic acid in both tradtional and commercial kochujang. Analysis of non-volatile organic acids showed that large amounts of lactic, oxalic, and succinic acids were found in traditional and commercial kochujang. In addition to these, small amounts of itaconic, malic, malonic, and pyroglutamic acids were found in commercial kochujang.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.4
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• pp.760-765
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• 1999

Changes in physiochemical properties of Sunchang sikhe kochujang, the most famous traditional kochujang, by red ginseng addition(1, 2 and 5% red ginseng on the total weight basis) were investigated. Measurements of physiochemical parameters such as reducing sugar content, alcohol content, amino type nitrogen content and color difference value were conducted during fermentation at 25oC for 120 days. Alcohol content was increased from the begining of fermentation, reaching at the highest level after 90 days of fermentation and then slowly reduced. Alcohol content of red ginseng kochujang was generally higher than that of control kochujang after 90 days of fermentation. Crude protein content of control kochujang and red ginseng kochujang were reduced during fermentation whereas amino type nitrogen content were gradually increased during fermentation. Amino type nitrogen content of red ginseng kochujang appeared to be slightly lower than that of the control kochujang. The reduction in amino type nitrogen content of red ginseng kochujang was negatively related to the level of red ginseng addition. Among color difference values, L and b value of both control kochujang and red ginseng kochujang were reduced by 30 days from the begining of fermentation and then started to be increased.

• Korean journal of food and cookery science
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• v.14 no.3
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• pp.219-224
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• 1998

Kochujang was prepared by using retrograded rice cakes (Song Pyun, Sym rice cake, Ssuk rice cake, Pat rice cake) as a source starch and the physiochemical and sensory characteristics were compared with traditional kochujang during aging for 60 days. Moisture content of all kochujang groups increased slowly but crude fat content decreased according to aging process. Changes of pH values of all kochujang reduced gradually during aging and the pH of saccharified kochujang was lowered than that of traditional one. Total reducing sugar contents in saccharified kochujang reached the maximum value at 50th day, and decreased thereafter. In contrast, the reducing sugar content in traditional kochujang was the highest at 30-day-aging. After 60 days of aging, the total contents of organic acids were 28.57 mg for P$\_$1/, 27.9 mg for P$\_$4/, 27.05 mg for P$\_$3/ 24.60 mg for P$\_$2/, and 22.30 mg for P$\_$0/. By sensory evaluation, saccharified kochujang prepared with Siru rice cake showed the highest sensory score in its appearance, flavor, texture, color, and taste.

• Korean Journal of Food Science and Technology
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• v.25 no.5
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• pp.494-501
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• 1993

The volatile flavor components of traditional and commercial kochujang were collected by simultaneous steam distillation-extraction (SDE) method. Essential oils were analyzed by gas chromatography (GC) and combined gas chromatography-mass spectrometry (GC/MS). Tested kochujang included Sunchang kochujang prepared with glutinous rice, Boeun kochujang prepared with barley, Sachun kochujang prepared with wheat and commercial kochujang. One hundred and twelve volatile flavor components which included 30 esters, 15 alcohols, 14 aldehydes, 13 acids, 9 ketones, 7 alkenes, 6 phenols, 3 alkanes, 3 pyrazines, 2 benzenes and 2 furans were identified. The major volatile compounds in traditional and commercial kochujang were 2-methyl propanal and ethanol, which represented $21{\sim}36%\;and\;2{\sim}44%$ of total GC peak area, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.1
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• pp.61-66
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• 1999

The purpose of this study was to improve the palatability of kochujang. The activities of liquefying amylase and saccharogenic amylase in Monacus anka koji were lower than those in Asp. oryzae koji. The acid protease activity(1.4 units/g) in M. anka koji was also lower than that(1.6 units/g) in Asp. oryzae koji. Glucosamine amount in Asp. oryzae koji was 1075 g, and that in M. anka koji was 318 g. Four kinds of Kochujang were prepared with Asp. oryzae koji(A), M. anka koji(M), mixed koji of Asp. oryzae and M. anka(A＋M), and mixture of M. anka koji and malt(M＋M). The pH of four kinds of kochujang was 5.1 in the beginning and was between 4.70~4.83 after 120 days of fermentation. Reducing sugar of kochujang was between 16.3~20.7% after fermentation and kochujang prepared with M＋M showed the highest reducing sugar content. Amino nitrogen of kochujang was between 182 mg%~230 mg% after fermentation and the highest amino nitrogen content was observed at kochujang prepared with A＋M. Kochujang prepared with M and M＋M showed higher a value than kochujang prepared with A and A＋M.

• Korean Journal of Food Science and Technology
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• v.36 no.1
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• pp.97-104
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• 2004

Effects of sub-materials such as, ethanol, mustard, and chitosan, on enzymatic, microbial and physicochemical characteristics of kochujang were investigated during fermentation. Activity of ${\alpha}$-amylase was low in chitosan-added kochujang, whereas those of ${\beta}$-amylase and pretense did not show any remarkable difference. Viable cells of yeast and bacteria decreased in sub-material-added kochujang during fermentation, with yeast counts decreasing more rapidly in ethanol- and mustard-added kochujang than that with chitosan. Consistency of kochujang decreased during fermentation, with the highest consistency observed in ethanol-added kochujang. Oxidation-reduction potential was low in chitosan-added kochujang. Water activity of all kochujang groups decreased during fermentation with the lowest in ethanol-added kochujang. Hunter L-, a-, and b-values of chitosan-added kochujang were higher than other groups, whereas increase in total color difference of low-salt without sub-material group was lowest pH of kochujang was the highest in ethanol-added kochujang, whereas titratable acidity increased remarkably in chitosan-added group. Total sugar and reducing sugar contents of kochujang were high in ethanol-and mustard-added groups, whereas ethanol production decreased remarkably in mustard-added kochujang. Amino nitrogen content was highest in low-salt without sub-material kochujang during late aging period. Ammonia nitrogen content was lower in mustard-added kochujang. After 12 weeks of fermentation, ethanol-added kochujang was more acceptable than mustard-and chitosan-added groups in taste, color, and overall acceptabilities.

• Korean Journal of Food Science and Technology
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• v.25 no.5
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• pp.502-509
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• 1993

Changes in microflora and enzyme activities of 3 kinds of traditional kochujang were investigated during 6 months of fermentation. Tested kochujang included Sunchang kochujang prepared with glutinous rice, Boeun kochujang prepared with barley and Sachun kochujang prepared with wheat. The pH in Sunchang and Sachun kochujang showed a slighlt decrese during fermentation. In contrast, pH of Boeun kochujang decreased rapidly up to 90 days of fermentation and then leveled off thereafter. The final pH values of Sunchang, Boeun and Sachun kochujang were 4.7, 4.0, and 4.6, respectively. The viable cell counts of aerobic bacteria in Sunchang and Sachun kochujang did not show remarkable changes during fermentation, however, those in Boeun kochujang showed a rapid increase up to 60 days of fermentation and stabilized. On the other hand, the viable cell counts of anaerobic bacteria decreased after 120 days of fermentation. Yeasts were found in different traditional kochujang at different time during the first 60 days of fermentation. It was found that ${\alpha}-$, ${\beta}-$, and glucoamylase activities of Sachun kochujang were higher than those of Sunchang and Boeun kochujang during fermentation. Acidic and neutral proteases showed the highest activity during $30{\sim}60\;days$ and $60{\sim}90\;days$ of fermentation, respectively. Sunchang kochujang showed the highest activity of acidic protease followed in decreasing order by Sachun and Boeun kochujang. On the other hand, Boeun kochujang showed the highest activity of acidic protease followed in decreasing order by Sachun and Sunchang kochujang.

• Food Science and Preservation
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• v.15 no.2
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• pp.214-218
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• 2008

In order to improve the quality of kochujang, sea tangle was added to deep sea water kochujang and their effects on component analysis and sensory evaluation were investigated for 90 days of fermentation. Crude protein, crude lipid and carbohydrate of deep sea water kochujang was higher than general kochujang. The content of potassium among the mineral in deep sea water kochujang was also presented higher than the general kochujang. Total amino acid contents were 16,608.8 ng/mg in deep sea water kochujang and 14,943.2 ng/mg in general kochujang. Content of oleic acid had the highest value at deep sea water kochujang. Sensory evaluation of showed that deep sea water kochujang were more aceeptable than general kochujang in the taste and overall acceptability.

• Korean journal of food and cookery science
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• v.21 no.5
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• pp.607-615
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• 2005

The purpose of this study was to analyze the characteristics of Chinese foods in main ingredients, sauces, and cooking methods, and to assess the applicability of kochujang in Chinese foods. Twenty Chinese foods and commercial kochujang were selected by a Chinese head cook. The main ingredients were 24 kinds such as pork, chicken, shrimp, bok choy, bean curd, Chinese noodles etc., which were generally used in Korean foods. The main Chinese sauces were 11 kinds, and soy sauce was used in 12 foods, shang loo tau soy sauce in 2, wine in 8, oyster sauce in 7, rice wine in 6. The classification of cooking units in all Chinese foods was performed and the cooking frequency was deep frying>pan frying>boiling>stir frying>steaming>roasting. The proper amount of kochujang (weight ratio) was decided by pre-test of the Chinese head cook and Chinese food added kochujang was assessed by a Chinese focus group. The overall preference of Chinese food added kochujang was assessed highly and was related to the kinds of sauces, and to the kinds of main ingredients. The foods which used soy sauce or shang loa tau soy sauce were preferred. Sweetness by using kochujang wasn't preferred in several foods. Saltiness and aftertaste by using kochujang didn't affect the food preference, and the intensity of color and pungency were evaluated as a moderate level. An increased amount of kochujang would be possible in several foods. However, the increase in the amount of kochujang for intensive color and pungency in Chinese foods was directly related to the increase of sweetness, which had been discussed as the main problem in lowering the preference. Therefore, the screening of various Chinese foods harmonized with kochujang and the determination of the proper mixing ratio with Chinese sauces are very important. The results of this study could be used as basic data for the promotion of kochujang consumption in the Chinese market.