• Food Science and Preservation
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• v.18 no.1
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• pp.18-25
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• 2011

We investigated changes in doenjang quality upon addition of rice fermented with Poria cocos mycelium. Sensory evaluation showed that rice addition to 15% (w/w) was optimal. The content of free amino acids was 1,899.17 mg% in doenjang fermented for 90 days with P. cocos mycelium. The rice contained seven essential amino acids: leucine, valine, phenylalanine, isoleucine, lysine, threonine, and methionine. The levels of essential amino acids increased after fermentation with P. cocos mycelium. Vitamin A (7.47 RE/100 g), Vitamin D (0.45 mg/100 g), and Vitamin E (5.73 mg/100 g) were detected in the experimental preparation but not in the control. In terms of electron-donating ability, the highest scores were 73.8% (in a water extract) and 76% (in an ethanolic extract) of doenjang fermented with P. cocos mycelium. Nitrite-scavenging ability was higher in the ethanolic extract than in the water extract of rice fermented with P. cocos mycelium.

• Journal of Microbiology and Biotechnology
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• v.21 no.12
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• pp.1270-1279
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• 2011

Bealmijang is a short-term aged paste made from meju, which is a brick of fermented soybeans and other ingredients. Different types of bealmijang are available depending on the geographic region or ingredients used. However, no study has clarified the microbial diversity of these types. We identified 17 and 14 fungal species from black soybean meju (BSM) and buckwheat meju (BWM), respectively, on the basis of morphology, culture characteristics, and internal transcribed spacer and ${\beta}$-tubulin gene sequencing. In both meju, Aspergillus oryzae, Rhizopus oryzae, Penicillium polonicum, P. steckii, Cladosporium tenuissimum, C. cladosporioides, C. uredinicola, and yeast species Pichia burtonii were commonly found. Moreover, A. flavus, A. niger, P. crustosum, P. citrinum, Eurotium niveoglaucum, Absidia corymbifera, Setomelanomma holmii, Cladosporium spp. and unclassified species were identified from BSM. A. clavatus, Mucor circinelloides, M. racemosus, P. brevicompactum, Davidiella tassiana, and Cladosporium spp. were isolated from BWM. Fast growing Zygomycetous fungi is considered important for the early stage of meju fermentation, and A. oryae and A. niger might play a pivotal role in meju fermentation owing to their excellent enzyme productive activities. It is supposed that Penicillium sp. and Pichia burtonii could contribute to the flavor of the final food products. Identification of this fungal diversity will be useful for understanding the microbiota that participate in meju fermentation, and these fungal isolates can be utilized in the fermented foods and biotechnology industries.

• Microbiology and Biotechnology Letters
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• v.51 no.2
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• pp.147-156
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• 2023

Tetragenococcus halophilus CY54, an isolate from jeotgal, grows best in media with 5% NaCl and can grow at 18% and higher salt concentration. Three different doenjang samples were prepared with multiple starters including T. halophilus CY54. TBZA doenjang was prepared with T. halophilus, Bacillus subtilis, Zygosaccharomyces rouxii and Aspergillus oryzae. BZA doenjang was prepared with the same 3 starters except T. halophilus. KACC doenjang was prepared with a single starter, B. subtilis KACC16750. During 16 weeks of fermentation at 25℃, the viable counts were maintained in the range of 7-8 log CFU/g in all 3 samples. As fermentation progressed, pH decreased and titratable acidity (TA) gradually increased. Crude protein contents decreased slightly. TBZA doenjang showed higher amino-type nitrogen (ANN) and volatile basic nitrogen (VBN) contents, and KACC doenjang showed higher ammonia-type nitrogen (AMN) content. TBZA doenjang showed higher fibrinolytic and protease activity than other doenjang samples. Metabolites analyses by GC/MS showed that doenjang samples were separated from each other by partial least squares-discriminant analysis (PLS-DA) analysis. Seventeen major metabolites involved in the differences between samples were identified and they included organic acids, amino acids, sugars, fatty acids and alcohols. TBZA doenjang showed higher contents for most metabolites responsible for flavor and taste of fermented foods including doenjang. These results showed that T. halophilus could be useful as a starter for doenjang and can improve the product quality by accelerating the fermentation processes.

• Microbiology and Biotechnology Letters
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• v.42 no.2
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• pp.99-105
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• 2014

A Bacillus strain capable of hydrolyzing locust bean gum was isolated as a producer of extracellular mannanase by way of an enrichment culture in an acidic medium from homemade soybean pastes. The isolate YB-1401 showed a biochemical identity of 61.1% with Brevibacillus laterosporus, while the nucleotide sequence of its 16S rDNA had the highest similarity with that of Bacillus amyloliquefaciens. The mannanase productivity of the Bacillus sp. YB-1401 was drastically increased by mannans. Particularly, maximum mannanase productivity was reached at approximately 265 U/ml in LB medium supplemented with konjac glucomannan (4.0%). The mannanase was the most active at $55^{\circ}C$ and pH 5.5. Mannanase activity was completely maintained after pre-incubation at pH 3.5 to 11.0 for 1 h. The predominant products resulting from the mannanase hydrolysis were mannobiose and mannotriose for LBG, guar gum or mannooligosaccharides. A small amount of mannose was also detected in the hydrolyzates.

• Journal of the Korean Society of Food Science and Nutrition
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• v.14 no.1
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• pp.67-71
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• 1985

Daenjang, a traditional Korean fermented soybean paste, was prepared by the fermentation with Aspergillus oryzae for 3 days, and then ripened with salt addition(13%) for 45 days. The changes of composition and fraction pattern of lipid in Daenjang during ripening period were studied. The total lipid of initial Daenjang(0 day ripening) consisted of 91.8% of neutral lipid, 7.1% of phospholipid and 1.1% of glycolipid, and minor changes of the composition were observed during the ripening. The contents of free fatty acid and esterified sterol in nonpolar lipid fraction were increased, however, no significant changes in polar lipid fraction were observed from the Daenjang in ripening. Linoleic, oleic, palmitic acids were the major fatty acyl moiety in the fractions of total lipid, triglyceride and free fatty acid, respectively. No significant changes in fatty acid compositions of the fractions were noted, although the saturated fatty acyl moiety of the fraction were increased a little during Daenjang ripening.

• Korean Journal of Food Science and Technology
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• v.40 no.3
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• pp.251-256
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• 2008

Eoyukjang is a traditional sauce-type of Korean food that is similar to a soybean sauce made from fermented soybeans, and it is produced from a fermented mixture of sea foods, meats, and meju (soybean paste). This study examined periodical changes in the enzymatic activities of ${\alpha}$-amylase, esterase, ${\beta}$-glucosidase, protease, lipase, and lipoxygenase within the culture broth and solids of eoyukjang during 1 year of fermentation. The eoyukjang solids had 234-532% higher protein content than the culture broth. The specific activities of ${\alpha}$-amylase, esterase, ${\beta}$-glucosidase, and protease increased in both the culture broth and solids. Particularly, in the culture broth, ${\alpha}$-amylase, esterase, ${\beta}$-glucosidase, and protease activities rapidly increased (3- to 8-fold) until 10 months of fermentation, and then drastically decreased. However, the activities of lipase and lipoxygenase in both the culture broth and solids were less than 0.05 unit/mg of protein, respectively, throughout fermentation; thus, their activity levels were low and changed little over the 12 months. Overall, while the solids had higher protein content than the culture broth, the broth had greater enzyme activity levels during eoyukjang preparation.

• Journal of Life Science
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• v.14 no.4
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• pp.553-559
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• 2004

To improve quality as a food source and functional properties of traditional fermented soybean paste (Doenjang), the Korean herb medicines (group I ∼ IV) extracted at 121$^{\circ}C$ for 2.5 hours were used as brine sources. Capsule Meju were fermented in cool brines with three different concentration (group A, B and C) of the extracts at room temperature for 3 months in large earthenware jars. The effect of traditional soybean Doenjang (refer as DHM below) supplemented with the extract of herb medicines on the food quality and chemical characteristics were examined. General composition of DHM (moisture 58.2%∼61.9%, pH 5.32∼5.56, total acidity 3.07∼3.70 ml, salt 11.7∼13.9%) did not differ from those of control (moisture 61.9%, pH 5.50, total acidity 3.25 ml, salt 12.6%). Concentration of reducing sugar, crude protein, crude lipid and amino type nitrogen were higher in DHM than those of control without addition of the extracts. Water insoluble-brown index showed no difference by the extracts. However, the former had higher water soluble-brown index than the latter, and within the DHM, groups I and II were higher than groups III and IV. Lightness values (L) of Hunter color index in groups I and II were 24.32 and 31.04, respectively. Redness values (a) of all DHMs were lower than that of control. Yellowness value (b) of groups III and IV were similar to that of control group, and Hunter b values of group I and II were lower than that of control.

• Nutrition Research and Practice
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• v.6 no.6
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• pp.520-526
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• 2012

Various forms of fermented soybean products are well documented for their health benefits. The efficacy of anti-obesogenic effect of Doenjang, one of the most commonly used seasonings in Korean cuisine, has been reported only in animal models; thus, an evaluation of Doenjang needs to be conducted in human studies. We aimed to test the hypothesis that Doenjang supplementation reduces body weight and changes body composition in overweight adults. A total of 51 overweight adults participated in this study. A group of males with BMI ${\geq}23kg/m^2$ and waist to hip ratio (WHR) ${\geq}$ 0.90, and a group of females with BMI ${\geq}23kg/m^2$ and WHR ${\geq}$ 0.85 were randomly assigned to either a Doenjang supplement (9.9 g dry/day) group or a placebo group for a 12-week randomized, double-blind and placebo-controlled study. Anthropometric parameters, abdominal fat distribution by computerized tomography (CT) and blood components were measured before and after the intervention period. After the 12-week study, the Doenjang supplementation group had significant reductions in body weight (kg), body fat mass (kg) and body fat (%) compared to the placebo group, the supplementation of Doenjang resulted in a significant reduction in visceral fat ($cm^2$), although no changes were observed in total and subcutaneous fat are as ($cm^2$), serum lipid profiles and dietary intakes. The present study demonstrated that daily supplementation of 9.9 g dry/day of Doenjang for 12 weeks reduces body weight and visceral fat in overweight adults.

• Korean Journal of Food Science and Technology
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• v.33 no.1
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• pp.94-99
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• 2001

Kochujangs(fermented hot pepper-soybean paste) were prepared either using traditional meju (koji for kochujang) or controlled meju fermented by pure isolates (P-1, P-2), which were screened from traditional meju collected at Sunchang area. The isolates were characterized for their superiority on amylase and protease activities, and overall flavor of the culture on cooked soybean. Bacterial cell counts were not different in all treatments of kochujang during fermentation. The mold counts of each treatment dropped to undetectable level after 40 and 60 days of fermentation, respectively. Heat treatment($60^{\circ}C$, 15 min) before fermentation stopped gas formation and had no effect on bacterial cell count, but the growth of yeast was depressed. Total accumulative volume of gas produced during kochujang fermentation was depended on load of yeast in kochujang and the kochujang using P-2 koji produced least amount of gas among all treatments. The amylase and protease activities of kochujang were not significantly different among traditional and controlled kochujangs.

• Korean Journal of Food Science and Technology
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• v.9 no.2
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• pp.131-137
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• 1977

This study was conducted to examine the changes of pH, proteolytic enzymic activity, and every kind of nitrogen compounds during their fermentation of the three groups of meju for 90days. Among the three groups, the first group was conventional Korean meju which was proved to be good quality (sample J), the second group was prepared with soybean paste using B. subtilis (sample K), and the third group was an improved meju which was fermented with the soybean and wheat (7 : 3) mixtured paste with Asp. sojae (sample L). These groups were analyzed at an interval of 10 day and the results are summarized as follows: 1) The pH of the all three groups was lowered from $6.45{\sim}6.75\;to\;4.85{\sim}5.20$ in just the 30 days and maintained the weak acidity during this fermentation. 2) The proteolytic enzymic activity was increased as soon as the three groups of meju were fermented and marked the maximum value in 30 days. The maximum value of the three groups of meju J.K. and L was 147, 112, and 52 respectively. The proteolytic enzymic activity of sample J and K was decreased to 23.5 and 20.5 in 20 days, while that of sample L was decreased to 18.0 in 40 days, and maintained the volues to the end of fermentation for 90 days. The conventional meju J and the improved meju K showed sparkling activity at the pH 7, while the activity of improved meju L was strong at the pH 10. 3) The PAA-N content of sample J and K was increased and reached to the peak point with 1.55% and 1.49% respectively in 60 days. But the sample L marked the maximum value with 1.28% after 80 days. 4) The amino-N content of sample J was increased and reached to 0.36% after 60 days, and that of sample K and L was increased and reached to 0.29% and 0.21% respectively after 40 days. After reaching to the peak point, the contents were decreased. 5) The content of ammonia-N was most abundant in sample K which was fermented with soybean paste using B. subtilis. 6) The peptide-N content of sample K and L was increased after decreasing in the middle of fermentation period, while that of sample J was increased gradually during fermentation. 7) The changes of nitrogen compounds were seemed to complete in 60 days of fermentation.