• Food Science and Preservation
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• v.15 no.1
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• pp.139-143
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• 2008

The potential use of Doenjang in place of salted-fish juice as an ingredient in Kimchi fermentation was examined, to improve Kimchi qualities such as flavor and taste. Quality characteristics were monitored during progressive fermentation of Kimchi with Doenjang (KD) at 7 d intervals for 28d at constant temperature $(10^{\circ}C)$. The data showed that the pH of KD was somewhat lower than that of the control as fermentation progressed. The titratable acidity in KD was linearly proportional to the pH change. Both the growth of lactic acid bacilli and total bacteria in Kimchi were inhibited in KD compared to control. In terms of color, the L, a, and b values of KD were all lower than those of control. In sensory evaluation, the taste, flavor, color, and overall acceptability of the new form of Kimchi were increased significantly by addition of 5 % (w/w) Doenjang (p<0.05). All data indicated that the color and taste properties of KD were improved by addition of Doenjang during fermentation.

• Journal of Life Science
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• v.27 no.12
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• pp.1486-1493
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• 2017

Doenjang is a traditional korean fermented soybean paste made from meju (fermented soybean), which are fermented by diverse microorganisms including Bacillus subtilis and molds such as Rizopus, Mucor, and Aspergillus species The purpose of this study was to investigate the antiobesity effect of the black soybean doenjang (Korean fermented soybean pastes) in C57BL/6 mice. The anti-obesity effect was determined by measuring the release of adiponectin, leptin and adipogenic transcription factors by using reverse transcription-polymerase chain reaction and western blot. Weight gain was significantly reduced in the mice fed high fat diets (HFD) plus black soybean doenjang (HBD) compared to HFD mice. The HBD were also effective in improving the lipid profile. They significantly decreased the levels of serum triglyceride and cholesterol. In addition, they had a significantly down regulated impact on antiobesity factors; leptin level and increased adiponectin level. Also, mRNA and protein expression of two adipogenic transcription factors, SREBP-1c and $PPAR-{\gamma}$, in high fat with black soybean fed mice were markedly down regulated. These results indicate that the black soybean doenjang potentiates an anti-obesity effect by modulating lipid metabolism, thereby inhibiting adipogenic transcriptional activation.

• Microbiology and Biotechnology Letters
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• v.47 no.3
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• pp.354-358
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• 2019

In order to evaluate the migration of fungi into doenjang from its materials, meju and solar salt, microbial communities were analyzed using pyrosequencing. Dominant fungi of meju were Botrytis spp. (57.94%) and Dothiorella samentorum (24.08%). Unidentified fungal species (37.53%), unassigned species (32.60%) and several fungal species of small portion were identified in solar salt. In doenjang, Candida versatilis were predominantly detected (92.62%). Non-halophilic mold were dominantly identified from meju (low-salt fermented soybean), while halophilic bacteria and archaea for solar salt and salt-tolerance fungi such as C. versatilis for doenjang (high-salt fermented soybean) were frequently detected. These results implied that most predominant fungal species might not be migrated from meju and/or solar salt into doenjang.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.5
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• pp.720-728
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• 2014

In order to characterize the quality of Doenjang, fermented Korean soybean paste, subjected to long-term aging, this study performed physico-chemical analyses and sensory evaluation according to aging period (from 1 to 9 years). Regarding the proximate composition of Doenjang according to aging period, moisture, crude protein, crude lipid, crude ash, and salt contents showed little differences among Doenjang samples. Amino-type nitrogen content was 1,046.7 mg% in the 1 year-aged sample, 990.9~996.9 mg% in the 2~5 year-aged samples, and 1,214.1~1,304.8 mg% in the samples fermented more than 5 years. ${\Delta}$E value, reflecting total color differences between the samples, increased according to aging period. Ratios of linoleic and linolenic acids, which are essential fatty acids in soybeans, constituted 55% of total fatty acids, which was the most abundant among all fatty acids. The major free sugar in Doenjang was fructose at a content of 1.6~2.2% in 1~9 year-aged Doenjang. Glycoside form of isoflavones in Meju constituted 77.1%, and the aglycon form constituted 22.9%. However, the glycoside type of isoflavones in soybeans was converted to aglycon type in Doenjang through fermentation and aging. In the sensory evaluation of Doenjang samples, brown color, salt smell, soy sauce flavor, and viscosity all increased according to aging period, whereas sweet flavor, roast smell, beany flavor, salty taste, and acrid taste showed no significant differences. In cluster analysis of the sensory attributes of Doenjang according to aging period, 1 year-aged Doenjang was significantly different between 2 year- and 3~5 year-aged Doenjang.

• Korean Journal of Microbiology
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• v.47 no.3
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• pp.275-280
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• 2011

In order to evaluate the diversity and change of bacterial population during the manufacturing process of traditional soybean paste (doenjang), bacterial communities were analyzed using 16S rRNA gene-based pyrosequencing. In rice straw, the most important inoculum source for fermentation, the bacterial sequences with a relative abundance greater than 1% were assigned to four phyla, Proteobacteria (71%), Actinobacteria (20.6%), Bacteroidetes (4.2%), and Firmicutes (1.3%). Unlike bacterial community composition of rice straw, a different pattern of bacterial population in meju was observed with predominantly high abundance (99.1%) of Firmicutes. Phylum composition in young doenjang was almost same as that of meju. Major genera in young doenjang were Bacillus (81.3%), Clostridium (6.9%) and Enterococcus (6.3%) and the predominant species among bacterial population was B. amyloliquefaciens (63.6%). Abundance of the phylum Firmicutes in mature doenjang was 99.98%, which was even higher value than those in meju and young doenjang. Predominant species in mature doenjang were B. amyloliquefaciens (67.3%), B. atrophaeus (12.7%), B. methylotrophicus (6.5%), B. mojavensis (3.2%), and B. subtilis. (2.5%), which were also identified as major species of the microbial flora in meju. These results suggested that rice straw was a primary source for supplement of Bacillus species in manufacturing the traditional doenjang and that some species of Bacillus strains were mainly involved in the fermentation process of traditional doenjang.

• Applied Biological Chemistry
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• v.38 no.1
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• pp.83-89
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• 1995

Changes in physical, chemical and microbiological characteristics of rice-doenjang prepared with two different methods with or without soak treatment were investigated during 60 days of aging at $32^{\circ}C$ and $15^{\circ}C$. The pH of soak-treated rice-doenjang decreased slowly, but that of nonsoak-treated rice-doenjang decreased rapidly at the initial aging stage with the aging temperature of $32^{\circ}C$, resulting in pH 5.1 after the 60 days of aging time. Reducing sugar contents increased up to the $30{\sim}50$ days of aging time and decreased thereafter. The contents of soluble nitrogen, formol nitrogen, ammoniacal nitrogen and amino nitrogen were more affected by preparation methods than by aging temperatures. Color values depended not only on preparation methods but also on aging temperatures. There were no significant differences in the bacterial counts of rice-doenjang, while apparent differences in the yeast and mold counts by aging temperatures were observed. These results suggested that the properties of soak-treated rice-doenjang were less changed than those of nonsoak-treated rice-doenjang by aging time and temperature. And, with a view point of nitrogen compounds, aging time could be reduced by soak treatment.

• Korean Journal of Food Science and Technology
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• v.43 no.3
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• pp.361-368
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• 2011

Three types of doenjang were prepared with regular soybean, germinated regular soybean, and a mixture of germinated regular and black soybean. After 90 days of fermentation, pH, moisture, and salt contents of doenjang were $6.01{\pm}0.01-6.72{\pm}0.01$, $53.78{\pm}0.22-57.99{\pm}0.11$, and $14.17{\pm}0.06-15.03{\pm}0.21%$, respectively, showing slight differences according to soybean germination. Amylase and protease activity of doenjang changed similarly during fermentation in all samples. Amino-type nitrogen and free amino acid content of germinated black soybean doenjang after 90 days of fermentation were $1256.21{\pm}1.86$ and 994.46 mg%, respectively, which were higher than those of other samples. A sensory evaluation of germinated regular soybean doenjang showed the highest scores for color, taste, and overall acceptability. These results suggest that high sensory quality doenjang can be prepared using germinated regular soybean and a mixture of germinated regular soybean and black soybean.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.2
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• pp.322-328
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• 2002

This study was carried out to investigate antimutagenic and anticancer effects of ethanolic extract of Korean traditional doenjang added sea tangle. Most of the mineral content of doeniang was increased by addition of sea tangle. In the Ames test, the antimutagenic effect of ethanol extract of Korean traditional doenjang added 5% sea tangle was higher than that of control (no additive), 10%, and 15% sea tangle additions. The inhibition rate of ethanol extract (200$\mu\textrm{g}$/plate) of doenjang added 5% sea tangle in the S. typhimurium TA100 strain showed 97.0% inhibition against the mutagenesis induced by MNNG. In addition, the suppression of ethanol extract (200$\mu\textrm{g}$/plate) of doenjang added 5% sea tangle in the S. typhimurium TA98 and TA100 strains showed 60.2% and 69.1% inhibition respectively, against the mutagenesis induced by 4NQO. The suppressions under the same condition against B($\alpha$ )P and Trp-P-1 in the TA98 and TA100 strains were 71.7% and 87.3%, and 66.6% and 80.8%, respectively. In the anticancer effects, the cytotoxicity of doenjang added 5% sea tangle on the cell lines with human lung carcinoma (A549), human hepatocellular carcinoma (HepG2), and human gastric carcinoma (KATOIII) were inhibited with increasing the extract concentration. The treatment of 1.0 mg/mL Doenjang added 5% sea tangle showed strong cytotoxicity of 56.4%, 87.67%, and 89.5% against A549, HepG2, and KATOIII, respectively.

• Korean journal of food and cookery science
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• v.10 no.1
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• pp.45-50
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• 1994

Conventional Doenjang, three kinds of Improved Doenjang(A; koji: soybean: salt=53: 100: 33, B; koji: soybean: salt=100: 100: 40, C; koji: soybean: salt= 200: 100: 40) prepared with different ratio of koji and salt were made to study the changes in the general contents, characteristics bitter peptides, correlations between bitterness and overall eating quality. 1. Total nitrogen contents increased a little, and amino nitrogen contents in all samples increase markedly. Especially, Amino nitrogen contents of conventrional Doenjang increased more than others. Reducing sugars of doenjang prepared with Asp. oryzae were higher than conventional Doenjang and increased throughout the aging period and Doenjang prepared with Asp. oryzae were more acidic. 2. To characterize bitter peptides in fermented Doenjang, peptides were extracted with 2: 1(v/v) chloroform-methanol and separated by Gel chromato-graphy with Sephadex and TLC. After Gel chromatography and TLC, each fraction examined presence of bitterness and evaluated intensity of bitterness. Amino acid composition of the fractions showing bitter tastes were as follows. Conv. peak 1-1 Trp-(Asp, Arg, Thr, Ser, Glu, Pro)-Phe Imp. A peak 1 Trp-(Glu, Val, Arg, lie)-Phe Imp. B peak 1 Trp-(lie, Pro, Asp, Lys, Val, Glu)-Trp. Imp. C peak 1-2 Trp-(Try, Thr, Glu, Pro, Gly)-Phe 3. Sensory evaluation revealed that correlation coefficient between bitterness and overall eating guality was not high.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.6
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• pp.944-950
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• 2015

The purpose of this study was to provide a basis for the management of traditional Doenjang by analyzing characteristics of volatile compounds in local Doenjang certified as a traditional food. The main compounds in Doenjang were acids, esters, aldehydes, and pyrazines, whereas relatively high intensities of acetic acid, ethyl alcohol, benzaldehyde, ethyl acetate, ethyl 2-methyl butanoate, 2,5-dimethyl pyrazine, and tetramethylpyrazine were detected among identified compounds. The analysis revealed that the composition of basic volatile compounds in Doenjang was similar, but isovaleric acid, 2-methylbenzaldehyde, tetramethylpyrazine, benzaldehyde, ethyl alcohol, ethyl caprylate, furfural and butanoic acid can serve as marker compounds for quality evaluation since they were specifically abundant in only some kinds of Doenjang. As a result, the quality status of Doenjang certified as a traditional food was determined by constructing a database of the volatile compounds, which can be suggested as a quality control method.