• Korean Journal of Food Science and Technology
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• v.42 no.3
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• pp.323-328
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• 2010

After supplemention with the licorice (Glycyrrhiza glabra), mustard (Brassica juncea), and chitosan as food additives to low-salted doenjang containing 30% lower salt than control doenjang (12.7% salt), fermentation properties of doenjang were investigated for 40 days. Adding the licorice, mustard, and chitosan to low-salted doenjangs containing 10.2% and 8.9% of salt did not affect the acidity, viable cell count, or color of doenjang. A white pellicle-forming strain was detected at the surface of low-salted doenjangs (10.2% and 8.9% salt) but not the control doenjang and low-salted doenjangs added with mixed additives (licorice, mustard, and chitosan). The amino nitrogen content of 8.9% salted doenjang added with mixed additives at 20 days was 332 mg% and this value was similar to that of 12.7% salted doenjang at 40 days. In sensory evaluation, the 8.9% salted doenjang added the additives had the highest score in overall palatability. These results indicate that salt contents of doenjang could be lowered to 8.9% by adding licorice, mustard, and chitosan, resulting in improved palatability, shortened fermentation period, and inhibited abnormal fermentation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.10
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• pp.1525-1530
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• 2015

Doenjang made with various concentrations of salt solution such as 13, 14, 15, 16, 17, and 18% for making low-salt Doenjang. Physicochemical and sensory characteristics of Doenjang made with various concentrations of salt solution were analyzed. As a result, salt contents of Doenjang made with various concentrations of salt solution were 6.09~13.47%. Amino-type nitrogen showed a higher value when prepared with lower salt solution. The pH value increased with lower concentration of salt solution, whereas total acidity decreased with lower concentration of salt solution. The pH values and total acidity of Doenjang made with more than 16% salt solution were not statistically different. The reducing sugar content ranged from 1.39~6.30 mg/g, and higher salt content was associated with higher reducing sugar content. In the sensory descriptive analysis, Doenjang had the most salty taste at a salt concentration of 18%, whereas Doenjang at concentrations of 15%, 16%, and 17% did not show any statistical differences. In the consumer acceptance test, Doenjang made with 17% and 18% salt solution showed the highest score, followed by Doenjang made with 15% and 16% salt solution. In conclusion, the salty taste of Doenjang made with 16% salt solution might be used to make low-salt Doenjang. However, consumer acceptance of these Doenjangs was lower than that of Doenjang made with 17% and 18% salt solution.

• Food Engineering Progress
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• v.15 no.4
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• pp.318-323
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• 2011

High pressure processing (HPP) technology was applied to inactivate the microorganisms in Doenjang (soybean paste) and the effects of salt concentration on the HPP inactivation of microorganisms were analyzed. The microorganisms in Doenjang containing low salt content showed greater sensitivity to HPP than those with high salt content. HPP inactivation effects decreased as salt concentration of Doenjang increased. The HPP sensitivity decreased in the order of fungi, yeasts, bacteria in terms of microorganism type. The HPP of Doenjang at 6,500 atm for 40 min inactivated most yeasts and fungi, indicating that the HPP technology was applicable to control the microorganisms in Doenjang, especially with a low level of salt.

• Food Science and Preservation
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• v.23 no.6
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• pp.788-796
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• 2016

This study presented the change of quality characteristics of Doenjang with various salt concentrations (4, 8, 15, and 20%) during 12 months. The pHs of Doenjang during fermentation were gradually increased for 12 months, whereas the pHs of Doenjang with 4 and 8% salt increased rapidly. Titratable acidity of Doenjang with 4 and 8% salt was high at initial time, while Doenjang with 15 and 20% salt was high at the 9 and 12 months. The amino-type nitrogen content of Doenjang with 4 and 8% salt was increased and ${\alpha}-amylase$ activity of all Doenjang was decreased during whole fermentation period. The protease activity of Doenjang with 4 and 8% salt was higher than Doenjang with 15 and 20% salt until 7 months. Total aerobic bacteria number 8.0~9.1 log CFU/g for 12 months, which was steady during fermentation period. Doenjang with 8% salt showed the highest score in umami taste whereas the lowest score in bitterness, astringency, and sourness tastes between 5 and 12 months. In conclusion, Doenjang with 8% salt was a suitable concentration for low-salt fermented foods.

• Journal of Microbiology and Biotechnology
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• v.26 no.4
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• pp.666-674
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• 2016

The bacterial strains were screened as potential starters for fermenting low-salt doenjang (a Korean traditional fermented soybean paste) using Korean doenjang based on proteolytic and antipathogenic activities under 6.5-7.5% NaCl conditions. Phylogenetic analysis based on 16S rRNA gene sequences showed that they all belonged to the genus Bacillus. Proteolytic and antipathogenic activities against Escherichia coli, Bacillus cereus, Staphylococcus aureus, Listeria monocytogenes, and Aspergillus flavus, as well as fibrinolytic, amylase, and cellulase activities of the 10 strains were quantitatively evaluated. Of these, strains D2-2, JJ-D34, and D12-5 were selected, based on their activities. The functional, phenotypic, and safety-related characteristics of these three strains were additionally investigated and strains D2-2 and D12-5, which lacked antibiotic resistance, were finally selected. Strains D2-2 and D12-5 produced poly-γ-glutamic acid and showed various enzyme activities, including α-glucosidase and β-glucosidase. Growth properties of strains D2-2 and D12-5 included wide temperature and pH ranges, growth in up to 16% NaCl, and weak anaerobic growth, suggesting that they facilitate low-salt doenjang fermentation. Strains D2-2 and D12-5 were not hemolytic, carried no toxin genes, and did not produce biogenic amines. These results suggest that strains D2-2 and D12-5 can serve as appropriate starter cultures for fermenting low-salt doenjang with high quality and safety.

• 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.

• Korean Journal of Food Science and Technology
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• v.34 no.1
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• pp.79-84
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• 2002

Changes of microbiological and physicochemical characteristics of gamma irradiated Doenjang with low salt were studied. Samples were prepared by mixing the Doenjang and the Chungkukjang with 6% and 8% of salinity. The mixture was irradiated by gamma-ray with dose of 0, 5, 10, 20 kGy, and each sample was stored at $25^{\circ}C$ for 8 weeks. The results showed that the Bacillus cell was inactivated by $10^4-10^5\;cells/g$ with dose of 10 kGy, and yeast and Lactobacillus group were nearly eliminated by 10 kGy. The general quality of gamma irradiated low salt Doenjang, such as amino nitrogen, protease activity, and pH, were more stable than that of control during storage periods. The sensory evaluations showed that 8% (salt)-5 kGy and 6% (salt)-10 kGy irradiated samples were more acceptable than market purchased Doenjang. Therefore, it was considered that gamma irradiation was effective for maintaining better quality of low salt Doenjang and suitable radiation dose was 5 kGy in 8% salted, and 10 kGy in 6% salted sample.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.4
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• pp.606-612
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• 1995

Three different Oyijangachi(Kochujang, Doenjang and Ganjang) have been prepared by traditional method. Cucumbers have been dipped in six different solutions for 48 hrs. After dipping, the cucumbers have been aged in Kochujang, Doenjang and Ganjang for 30 days. The acidity, pH, salt content and sensory evaluation of the cucumbers which were treated by six different solutions has measured. Moisture content of fresh cucumber was 95%, and the moisture content of Kochujang, Doenjang and Ganjang of Oyijangachi was 66.78%, 76.94% and 81.33%, respectively, after 30 days of aging. Protein content fo Kochujang, Doenjang and Ganjang of Oyijangachi increased 57%, 258% and 197%, respectively, after 30 days of aging when they compared with fresh cucumber(control). Initial acidity of Oyijangachi of cucumbers which were treated with solution 1~5 at 0 day were between 0.49 and 0.56 and increased during aging. Initial acidity of Oyijangachi treated with solution 6 was 1.84 which was low because 1% of acetic acid was added and acidity increased during aging. The pH of Kochujang, Doenjang, and Ganjang of Oyijangachi decreased 4.37, 3.98 and 4.61, respectively, after 30 days aging. Salt content of Oyijangachi dipped in various salt solutions increased as the salt content of the solution increased. Salt content of three Oyijangachi increased drastically during 0~5 days of aging and slowly increase between 5~30 days of aging. The taste and smell of Kochujang Oyijangachi were highest as treated wih 12% NaCl solution(treatment 4) and the color was highest when the Oyijangachi was treated with solution 1. The taste, smell and color of Doenjang Oyijangachi were highest as treated with 12% NaCl solution plus CaCl2(treatment 5). It was observed that the firmness of Oyijangachi was generally higher as the cucumber treated.

• Food Science and Preservation
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• v.21 no.5
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• pp.627-635
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• 2014

We investigated the changes in the quality characteristics of Doenjang with low salt contents (6, 8, 10, and 12%) and 10% garlic. The Doenjang was analyzed at an interval of a week during its fermentation for six weeks, at room temperature. Its L color gradually decreased, but its a and b colors did not change significantly. Its salinity increased by about 1% after six weeks. In contrast, immediately after its preparation, its pH was gradually decreased and its acidity was increased for the fermentation. The reducing sugar was significantly increased from 1.34~1.88 g/100 g immediately after its preparation to 7.25~9.13 g/100 g after six weeks, which was higher as the salt concentration decreased. The amino-type nitrogen doubled from 100~130 mg% at 0 week to 210~290 mg% at six weeks, which were lower with the higher salt concentrations. The growth curve of the Bacillus fermentation strains of Doenjang increased to two weeks but gradually decreased since, and the growth of the Bacillus was favorable for up to two weeks in the Doenjang with 10% and 12% salt added. Otherwise, the yeast was reduced rapidly during the early fermentation of the Doenjang, and slightly changed after three weeks of fermentation. The results of this study showed that the reducing sugar and amino-type nitrogen contents of the low-salt garlic Doenjang were higher with the lower salt dose, and the physicochemical quality of the 6%-salt Doenjang was not significantly affected. Thus, we suggest that low-salt Doenjang can be manufactured with the addition of 6% salt and 10% garlic.

• The Korean Journal of Food And Nutrition
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• v.29 no.5
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• pp.785-794
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• 2016

This research was conducted to evaluate quality changes in traditional Doenjang and manufactured Doenjang during a storage period of 8 weeks. Low-salt Doenjang and commercial Doenjang were purchased from different manufacturers and proximate analysis as well as changes in isoflavone, polyphenol, flavonoid contents of the samples were investigated using a mass spectrophotometer. The salinity of traditional Doenjang, low salt Doenjang, and commercial Doenjang were $13.2{\pm}1.15$, $7.17{\pm}2.74$, $10.67{\pm}0.35%$, respectively and the salt concentrations of the soybean pastes did not change during storage. After 8 weeks at $35^{\circ}C$, chromatic values of all the paste samples decreased somewhat, with traditional Doenjang exhibiting fewer changes as compared to manufactured Doenjang. Amino acid nitrogen, acidity, microbial population all tended to increase with time, although some samples showed fluctuations during the test period. Moreover, the total isoflavone contents of traditional Doenjang increased with storage time while that of manufactured Doenjang tended to decrease. The isoflavone aglycone was shown to be the highest in traditional Doenjang, while isoflavone glycoside was abundant in manufactured Doenjang. Total flavonoid contents showed similar trends regardless of samples; initial contents of total flavonoid was 0.6 mg/g which increased to more than twice to 1.4 mg/g at the end of storage period. Composition profile of Doenjang extracts was analyzed using UPLC-Q-ToF.