• Korean Journal of Food Science and Technology
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• v.26 no.5
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• pp.609-615
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• 1994

Fermented traditional soybean paste(doenjang), koji soybean paste by Aspergillus oryzae, natto soybean paste by Bacillus natto and koji & natto soybean paste by Aspergillus oryzae and Bacillus natto were analyzed for compositions of amino acids and contents of nitrogens. Amino type nitrogen was the highest in fermenting for 90 days as $271{\sim}868\;mg/100g$, and its contents were in the order of koji soybean paste>traditional soybean paste>koji & natto soybean paste>natto soybean paste in all samples tested. In compositions of total amino acids, glutamic and aspartic acids were rich in koji soybean paste but big differences were not observed in all samples. But some differences were observed in free amino acid compositions in all samples, that is, glutamic acid, tyrosine, lysine and aspartic acid were detected more abundantly. Sum of free amino acids for 90 days were in order of koji soybean paste>traditional soybean paste>koji & natto soybean paste>natto soybean paste. The ratios of free to total amino acids were $3.28{\sim}19.81%$ for 45 days, but increased to $10.88{\sim}25.10%$ for 90 days, and in order of traditional doenjang>koji doenjang>koji & natto doenjang>natto doenjang. Methionine and histidine showed higher ratios of free to total amino acid but lower in glutamic acid and aspartic acid. These results suggest that koji and traditional soybean paste of having high ratios of free amino acids to free and total amino acids may be more favorable in soybean paste fermentation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.6
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• pp.917-924
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• 1995

Four types of soybean paste(Doenjang), prepared with traditional Korean meju, natto meju, koji and mixture of koji and natto meju, were analyzed for compositions of free sugars and fatty acids. Crude protein content of the soybean pastes were ranged from 10.3~14.6% and in the order of traditional Korean soybena paste>natto soybena paste>koji & natto soybean paste>koji soybean paste during fermentation of Doenjang. Ethyl alcohol contnet was relatively higher in koji and natto soybean paste after fermentation for 75 days, and its content was the highest in koji soybean paste as 2.8% after fermenting for 90 days. Contents of total sugars and reducing sugars decreased during fermentation of doenjang in the order of koji soybena paste>koji and natto soybean paste>traditional soybean paste>natto soybean paste. Among the free sugars glucose, galactose, mannose and arabinose were identified in soybean paste, and glucose and galactose were more bundant. Contents of glucose and total free sugars were the highest in the traditional Korean soybean paste and galactose content was highest in koji soybean paste. In fatty acid compositions of soybean pastes, palmitic, stearic, oleic, linoleic, linolenic and arachidonic acids were analyzed, and the most abundant fatty acid was found to be oleic acid as 38.5~46.9% in all samples tested. But no significant differences in ratio of fatty acid compositions was observed from tested samples during the fermentation period.

• Korean journal of food and cookery science
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• v.26 no.3
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• pp.314-322
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• 2010

The effects of five colored soybean (blue, red, yellow, white, and black) varieties on the quality characteristics of soybean paste (Doenjang) were investigated for proximate composition, salt content, pH, color, organic acid content, amino acid content, and mineral content after 80 days of aging. Soybean paste (Doenjang) samples were divided into TDS (traditional Doenjang prepared with soybean) and TDM (traditional Doenjang prepared with mixed soybeans, kidney bean, black soybean, kind of small bean, sword bean, green bean, red bean, at a radio of 1:1:1:1:1(w/w)). Moisture content was 49.66% for TDM and 49.52% for TDM. Protein and salt contents of the TDS sample were higher than those of TDM. The "L" values of the TDB sample increased the aging period was decreased. In contrast, the "L" and "$\alpha$" values of TDM did not show any significant differences. The main organic acids detected were malic acid > lactic acid > tartaric acid in the TDS and TDM samples. Glutamic acid contents were 2.83 g/100 g for the TDS sample and 2.15 g/100 g for the TDM. The levels of K, Mg, and Ca of the TDS sample were higher than those of TDM. No significant difference occurred between TDS and TDM regarding their quality characteristics after 80 days of aging. Further studies needed include sensory evaluation and functionality of soybean paste made from mixed soybean materials.

• Korean Journal of Food Science and Technology
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• v.26 no.3
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• pp.255-260
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• 1994

Four types of soybean paste(Doenjang), using traditional meju, koji, natto meju and mixture of koji and natto meju, were manufactured and fermented for 90 days. Analyzed volatile flavor components by GC-MS were confirmed to be thirty-six components including 5 alcohols, 5 aldehydes. 8 ketones, 3 acids, 9 esters and 6 miscellaneous ones. Traditional soybean paste tested had 29 components, koji and koji-natto soybean paste $26{\sim}24$ and natto soybean paste had 20 ones. Alcohol was found to be the most abundant volatile flavor components in all samples group. Traditional soybean paste had higher ratio of carbonyl to ester than any other types of soybean paste while koji-natto soybean paste had the lowest ratio of their components. The newly identified five volatile flavor components were 3-ethoxy-l-propene, dihydro-2-methyl-3-furanone. 1-hydroxy-2-propanone, 1-(2-furanyl)ethanone and 2-acethyl ethylhexanoate.

• Korean Journal of Food Science and Technology
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• v.34 no.3
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• pp.400-406
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• 2002

In case of doenjang, solution of browning problem might be an important remedy in order to dissolve consumers' dissatisfaction, therefore this study was performed to develop traditional doenjang which has improved in color aspect for consumers' needs. Physicochemical compositions and color values of commercialized traditional doenjang which was processed by history references of our country, were analyzed. doenjang used as samples were processed with traditional meju, which were made with soybean and mixed with various rates after following process such as soaking, steaming, cooling, chopping and grinding. The doenjang processed were storaged at $30^{\circ}C$ for 27 days, and their amino-N, pH, color values and sensory evaluation were analyzed with fermentation period. Furthermore, nitrogen results analyzed were compared with that of commercialized traditional doenjang. In the comparison with control, treated with only traditional meju, and doenjang treatments processed with different mixing rates of traditional meju and steamed soybean, the content of amino-N in control were higher than the others, and the contents of amino-N decreased with increasing contents of steamed soybean. Their pH were changed weak alkalic region into weak acidic region with fermentation period. In the aspect of color, traditional doenjang having the rate of traditional meju and steamed soybean (1:4) was most improved and also, in comparison of result of sensory evaluation with commercial traditional doenjang, its color, taste and falvor were evaluated predominent, therefore it might be thought to have competition on the market.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.3
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• pp.375-384
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• 2011

The effects of mixed beans on quality characteristics of traditional soybean paste (Doenjang) were investigated. The proximate composition of the soybean paste (Doenjang) met traditional food standard requirements. The range in salinity was 12.30~13.20%, and the salinity decreased with an increase in the amount of mixed beans. A significant difference in pH values occurred in all samples(p<0.05). The Hunter's 'L ($45.06{\pm}0.41$)' and 'b ($13.89{\pm}0.73$)' values of the TDM2 samples were higher than those of other samples. The highest amounts of malic acid of the organic acids are shown. The order of the amino acid content was aspartic acid > leucine > lysine, and that of free amino acid contents were proline > glutamic acid > arginine. The order of mineral content in the soybean pastes was Na > K > Ca > Mg, but levels of Co, Cu, and Zn were not detected. The traditional soybean paste (Doenjang) had an effective DPPH radical scavenging activity and higher phenolic content compared to those of the control sample. Overall acceptability score of the TDM2 (soybean 1 : mixed beans 1) was higher than that of the others. More research is needed to enhance the quality and functionality of traditional soybean paste.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.6
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• pp.980-985
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• 1994

We investigated the quality of soybean paste(Doenjang) fermented by BAcillus brevis. The results obtained were as follows : soybean paste fermented by Bacillus brevis had alkaline pH and yellow ochre color. Dextrinizing activity was about 98 D.P. unit from 5th to 25th day of fermentation at 3$0^{\circ}C$ and after that day somewhat decreased . Saccharifying activity was respectively 6.1, 7.2, 6.8, 6.4 S.P. unit on 5, 15, 25 and 35th day of fermentation. Protease activity suddenly increased after 15th day of fermentation and was 250, 275, 299 unit on15, 25, 35 th day of fermentation , respectively. The most abundant free amino acid was found to be glutamic acid (561.8mg%) in soybean paste fermented by Bacillus brevis. In case of free sugar and non-volatile organic acid, fructose and oxalic acid showed highest content of 10.25mg% on 25th day and 12.20mg% on 15th day. The contents of free amino acids, free sugars, organic acids in soybean paste fermented by B.brevis were most abundant after 25 days of fermentation and this results were similar to that of traditional soybean paste. The odor of soybean paste fermented by Bacillus brevis was improved to be a nice soybean paste odor on 25th day of fermentation. However, sensory evaluation value of the taste of it decreased after 10 th day of fermentation.

• Korean journal of food and cookery science
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• v.32 no.6
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• pp.686-695
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• 2016

Purpose: This study aimed to investigate the quality characteristics of traditional and commercial soybean pastes (Doenjang) for development of traditional soybean pastes. Methods: Proximate compositions, amino acid nitrogen contents, pH, acidity, salt contents, chromaticity, viable bacteria and inorganic substance contents of nineteen traditional and three commercial Doenjang were investigated. Results: Analysis of proximate compositions indicated a significant difference between samples. In moisture content, D10 did not meet the standard of food codex. The contents of moisture, fat, protein and ash were slightly higher in traditional than commercial Doenjang. However, the carbohydrate content was 2-fold higher in commercial than traditional, and thus, the calories were also higher. The amino nitrogen content was lower in commercial than traditional Doenjang. pH, acidity and salt contents of Doenjang were pH 4.67-6.15, 1.53-3.29%, and 9.01-18.78%, respectively. pH and acidity showed no significant differences between traditional and commercial Doenjang, however, salt contents were significantly higher in traditional than commercial Doenjang. In case of chromaticity, the averages of L, a, b values were higher in traditional Doenjang. In microbiological analysis, total bacteria counts were higher in traditional than commercial Doenjang. The number of Bacillus cereus in D12 and D19 exceeded the standard of food codex. Staphylococcus aureust was undetected in all samples. The number of fungi varied widely between samples, with no detection in five traditional and all commercial Doenjang. Results of inorganic substance analysis indicated that contents of inorganic substances in Doenjang were in order of Na, K, Mg and Ca. Overall, Na content was higher in traditional Doenjang. Contents of inorganic substances showed wide variations in traditional Doenjang. Conclusion: For the development of traditional Doenjang, quality standardization and ensuring safety are considered necessary.

• Microbiology and Biotechnology Letters
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• v.44 no.1
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• pp.40-47
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• 2016

This study was conducted to evaluate the possible utility of 3 Aspergillus oryzae strains (designated as SCF-6, SCF-37, and JJSH-1), isolated from Korean traditional fermented materials, as starter cultures in the soybean paste industry. Doenjang (fermented soybean paste) was made with the A. oryzae strains described above, and its quality attributes were analyzed during a 60-day aging period. No significant differences in pH, moisture, or salt content were detected among the doenjang varieties made with the 3 Aspergillus strains. The concentration of amino-nitrogen, an indicator of doenjang aging, increased in each sample during the aging period. After the 60-day aging period, the contents of amino-nitrogen and free amino acid in doenjang made with SCF-6 showed the highest concentrations among the tested doenjang products: 971.6 and 8,064.9 mg%, respectively. Measurements of the color of doenjang showed that lightness and yellowness decreased during the aging period, but redness increased. After the 60-day aging period, the ${\gamma}$-aminobutyric-n-acid (GABA) concentrations in doenjang made with SCF-6 and SCF-37 were 61.3 and 53.7 mg%, respectively. In doenjang samples, aflatoxin was not detected and the concentrations of biogenic amines (histamine and tyramine) were 2.55-5.60 mg/kg and 3.70-5.87 mg/kg, respectively. These results indicated that A. oryzae SCF-6 isolated from traditional fermented foods could be useful as a starter culture in the soybean paste industry.

• Nutrition Research and Practice
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• v.9 no.3
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• pp.235-241
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• 2015

BACKGROUND/OBJECTIVES: Doenjang, Korean traditional fermented soybean paste has been reported to have an anti-obesity effect. Because adipose tissue is considered a major source of inflammatory signals, we investigated the protective effects of Doenjang and steamed soybean on oxidative stress and inflammation in adipose tissue of diet-induced obese mice. MATERIALS/METHODS: Male C57BL/6J mice were fed a low fat diet (LF), a high-fat diet (HF), or a high-fat containing Doenjang diet (DJ) or a high-fat containing steamed soybean diet (SS) for 11 weeks. RESULTS: Mice fed a DJ diet showed significantly lower body and adipose tissue weights than those in the HF group. Although no significant differences in adipocyte size and number were observed among the HF diet-fed groups, consumption of Doenjang alleviated the incidence of crown-like structures in adipose tissue. Consistently, we observed significantly reduced mRNA levels of oxidative stress markers (heme oxygenase-1 and $p40^{phox}$), pro-inflammatory adipokines (tumor necrosis factor alpha and macrophage chemoattractant protein-1), macrophage markers (CD68 and CD11c), and a fibrosis marker (transforming growth factor beta 1) by Doenjang consumption. Gene expression of anti-inflammatory adipokine, adiponectin was significantly induced in the DJ group and the SS group compared to the HF group. The anti-oxidative stress and anti-inflammatory effects observed in mice fed an SS diet were not as effective as those in mice fed a DJ diet, suggesting that the bioactive compounds produced during fermentation and aging may be involved in the observed health-beneficial effects of Doenjang. CONCLUSIONS: Doenjang alleviated oxidative stress and restored the dysregulated expression of adipokine genes caused by excess adiposity. Therefore, Doenjang may ameliorate systemic inflammation and oxidative stress in obesity via inhibition of inflammatory signals of adipose tissue.