• Korean Journal of Food Science and Technology
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• v.30 no.5
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• pp.1000-1005
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• 1998

To establish the process control for inhibiting browning of Doenjang, the factors of browning were investigated. The browning of Doenjang was prompted by oxygen, temperature, light and Fe. Expecially temperature, oxygen and metal were main factors of browning in Doenjang. The Color Doenjang was determined by ratios of raw materials, process of manufacture and the channel of distribution. Among ascorbic acid and anti-browning agent, anti-browning agent was effective to inhibit the browning of Doenjang. The process control to inhibit the browning of Doenjang was as follows: temperature; $20^{\circ}C$ or less than, oxygen; elimination, Fe; inhibition of inflow.

• The Korean Journal of Food And Nutrition
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• v.31 no.2
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• pp.264-271
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• 2018

The objective of this study was to investigate taste profiles and the correlation of Doenjang soup solution prepared with three different temperatures (5, 25, $45^{\circ}C$) and using an electronic nose (e-nose), electronic tongue (e-tongue), and descriptive analyses by trained panelists. A total of 17sensory attributes were generated from the descriptive analyses for the Doenjang soup solution. There were significant difference among the samples in the cooked soybean flavor, the cooked soybean odor, the soy sauce odor, the sweet odor, the sweet taste, and the sweet aftertaste attributes. The intensities of these sensory attributes tended to increase as the serving temperature of the Doenjang soup solution increased. There were seven volatile compounds detected by the electronic nose: ethanol, propanal, 2-methylpropanal, ethyl acetate, 3-methylbutanal, and beta-pinene. The intensities of the volatile compounds increased as the temperature of the Doenjang soup solution increased. On the other hand, the intensities of the basic tastes by the e-tongue decreased as the temperature of the Doenjang soup solution increased. In conclusion, the e-nose, e-tongue, and descriptive analysis results showed different correlations depending on the temperature of the Doenjang soup solutions.

• Journal of Applied Biological Chemistry
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• v.61 no.4
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• pp.357-365
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• 2018

The quality of Korean doenjang, which was traditionally made for this study, was monitored for physicochemical properties, antioxidant capacity, and sensory properties at six months intervals for three years. The collected data were comprehensively analyzed using the k-means clustering via principal component analysis (PCA) to determine the optimal intake duration and sensory factors associated with acceptance. Doenjang samples were classified with every year interval based on PCA, and then the classified doenjang samples were further grouped into cluster one, two, and three based on the k-means clustering. In Cluster three, doenjang that was aged for thirty and thirty-six months, respectively, showed high total phenolic content, antioxidant capacity, superoxide dismutase like activity, and 2,2-diphenyl-1-picryl-hydrazyl radical scavenging capacity. Interestingly, along with acceptance, the levels of free amino acids and organic acids were higher in Cluster 3. The sensory factors found to be associated with acceptance included umami taste and brown color. In conclusion, this study proposes the intake of doenjang aged for thirty months based on its antioxidant activity and sensory properties although doenjang is usually ready after twelve months of aging.

• Food Science and Biotechnology
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• v.17 no.5
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• pp.1021-1024
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• 2008

Genistein, one of the isoflavones in doenjang, is generally known to prevent various cancers, osteoporosis, climacterium, and menopause symptoms, and has better bioavailability and healthful physiological effects than its glucoside, genistin. In both traditional and commercial doenjangs, genistein content ranged from 370 to 1,510 mg/kg, however, significant amounts of genistin also existed at the level of 190 to 350 mg/kg. After treating with corn $\beta$-glucosidase, over 84% of genistin in doenjang was converted to genistein. However, physiochemical characteristics such as pH, viscosity, 2-thiobarbituric acid (TBA) value, and color were not changed significantly after corn $\beta$-glucosidase treatments. Therefore, this study shows that the improved doenjang with the increased genistein content can be produced using corn $\beta$-glucosidase.

• Journal of Applied Tourism Food and Beverage Management and Research
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• v.13 no.1
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• pp.55-68
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• 2002

Flow properties of doenjang samples at various total solid contents (30, 32, 34, 36, 38, 40%) were evaluated in this study. Flow properties of doenjang samples was determined by using Haake concentric cylinderical viscometer and Instron testing machine with capillary extrusion viscometer, and consistency index(K), and flow behavior index(n) was also determined from power models, and yield stress was derived form Casson models and vanes methods. Doenjang samples showed shear-thinning (pseudoplastic) fluid with small magnitude of flow behavior index(n) (n=0.30-0.55). Casson yield stress was from 2.11 to 64.02(Pa). Vane yield stress was more effective than casson yield stress in property of reactivation. Apparent viscosity was decreased with the increase in temperature and activation energy was in the range of 6.58 to 10.70 kJ/mole. From the capillary extrusion method, K and n was increased with the increase in solid content with good correlation with. The result revealed that capillary extrusion method is useful for measuring the flow properties of doenjang.

• Food Science and Biotechnology
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• v.18 no.4
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• pp.1030-1034
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• 2009

A fermenting microorganism involved in formation of ortho-dihydroxyisoflavones (ODIs) during aging of doenjang (Korean fermented soybean paste) has been investigated. Microorganisms in ODI-containing doenjang were isolated by cultivating on yeast mold (YM) agar medium containing 0-7% NaCl. ODI formation of the isolated strains was examined by gas chromatography/mass spectrometry (GC/MS) analysis after cultivation in modified YM broth or soybean extract medium. An ODI-producing microbe was identified as Bacillus subtilis HS-1 based on 16S rRNA gene sequence analysis. The strain has produced 8-hydroxydaidzein as a major product during growth in the modified YM broth or soybean extract medium. Therefore, it was concluded that one of the microorganisms involved in the formation of ODIs in doenjang was B. subtilis HS-1.

• Journal of Microbiology and Biotechnology
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• v.7 no.1
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• pp.75-80
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• 1997

An ethanolic fermentation process was developed for preparing Doenjang with high ethanol. Higher and efficient viable cell production of salt-tolerant ethanolic yeast is a prerequisite for the successful commercial-scale process of ethanol production during Doenjang fermentation. Culture conditions of salt-tolerant yeast, S. cerevisiae KFCC 10823, was studied in terms of the effect of several environmental and nutritional factors. Viable cell numbers were the highest in a medium containing the following components per liter of water: soysauce, 300ml; dextrose, 50 g; beef extract, 5 g; yeast extract, 5 g; $KH_2PO_4$, 5 g; NaCl, 50 g. The optimal culture conditions of S. cerevisiae KFCC 10823 were pH 5.5, $25^{\circ}C$, 200 rpm and 0.5 vvm. Yeast viability during batch fermentation was gradually decreased to a level less than $90{\%}$ after 35 hours. The maximum cell number was $2.2{\times}10_7$ cells/ml at the optimal condition. Doenjang prepared with ethanolic yeast was ripened after 45 days at $30^{\circ}C$. This Doenjang contains 470 mg% of amino nitrogen and 2.5% ethanol. The shelf-life at $30^{\circ}C$ was theoretically estimated as 444 days.

• Preventive Nutrition and Food Science
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• v.17 no.2
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• pp.172-176
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• 2012

Doenjang is a traditional Korean fermented soybean product that provides a major source of protein. In this study, a total of 18 different home-made doenjang samples were examined for the presence of foodborne pathogens and the total aflatoxin levels. Using an enzyme-linked immunosorbent assay to assess microbial quality and potential public health risk, we showed that total coliform levels in the doenjang samples ranged from 0 to $4.43{\pm}2.32{\times}10^6\;CFU/g$, and the maximum limit of Bacillus cereus was $4.67{\pm}2.0{\times}10^5\;CFU/g$. However, other foodborne pathogens, such as Staphylococcus aureus, Escherichia coli O157:H7 and Salmonella spp., were not detected among the tested samples. One of the samples (S3) showed a maximum limit of $42.2{\pm}9.1\;{\mu}g/kg$ for aflatoxin levels, which was above the safety limit allowed by the Codex Alimentarius Commission (CAC) regulatory agency. Further research is necessary to determine whether and how doenjang safety can be improved via elimination/reduction of microbial contamination during fermentation and storage or using microbial starter cultures for its fermentation.

• The Korean Journal of Food And Nutrition
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• v.12 no.4
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• pp.350-357
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• 1999

To investigate the consumption pattern of traditional fermented soybean products a survey was con-ducted to the subjects composed of 308 housewives in busan yangsan and ulsan. Doenjang was rated among one of the often-used traditional foods in Korean meal preparation. 67.2% fo the respondents used Doenjang once or twice a week and 22.7% every day and by the educational level the lower in education level used more. Doenjang has been prepared by housewives themselves(46.9%) or by their relatives(30.7%) for the most important reason of good taste and by purchasing of commercial products(22.4%) for convenience. By regional groups the frequency to use commercial products of Doenjang was higher in Ulsan and the younger or the higher in education level showed the higher frequency. The consump-tion pattern of Gochujang was very similar to that of Doenjang. Chunggukjang which has peculiar flav-our showed very low consumption with being rarely used or having not eaten by 60.3% of subjects. Gan-jang was consumed mainly once or twice a week and jin-ganjang was preferred than Guk-ganjang. In the preparing methods Guk-ganjang have been made by housewives themselves(31.0%) by their relativ-es(29.5%) or by purchasing of commercial products(31.0%) and Jin-ganjang mainly by purchasing of commercial products(65.0%) which showed higher consumption frequency of commercial products com-pared with Doenjang and Gochujang.

• Food Science and Preservation
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• v.24 no.7
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• pp.923-933
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• 2017

This study was carried out to examine the quality characteristics of Doenjang manufactured with or without soaking Meju in brine according to salt concentrations (8 and 12%) during fermentation for 6 months. The moisture content and salinity of Doenjang fermented for 6 months were 54.9-60.3% and 7.8-12.5%, respectively. Doenjang using soaking Meju in brine had higher pH and lower titratable acidity than that using non-soaking Meju. The reducing sugar content in all samples was increased until 2 months and then decreased regardless of soaking Meju, especially that of non-soaking 8% Doenjang was the highest. The 8% low-salt Doenjang was shown the highest amino-type nitrogen content, especially the soaking Doenjang was higher than the non-soaking Doenjang. ${\alpha}$-amylase activity of all samples during fermentation were continuously decreased from 0.91-0.94 Unit/g to 0.01-0.06 Unit/g, especially the 8% soaking Doenjang was shown the highest activity after 2 months. Total bacterial count of the soaking Doenjang at the 6 months was in range of 7.8-8.0 log CFU/g and that of the non-soaking Doenjang was in range of 7.2-7.5 log CFU/g. By taste analysis, the 8% soaking Doenjang was shown the similar taste pattern with commercial Doenjang. In conclusion, the 8% low-salt Doenjang manufactured with soaking Meju in brine was a suitable concentration in order to reduce salt intake.