• 한국식품영양과학회지
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• 제27권3호
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• pp.448-454
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• 1998

Meju for doenjang and kochujang was prepared as a model at Sunchang areaand monitored with major changes. Kochujang meju was prepared on September 12 and doenjang meju on November 12, 1995. Kochjang meju was found to be naturally fermented at 80~90% RH, 15~2$0^{\circ}C$ and doenjang meju was at 80~90% RH and 0~5$^{\circ}C$. The shapes of kochujang meju and doenjang meju were doughnut-type and rectangular, respectively. Weight losses during fermentation were 48% and 28%, respectively. The pH drop and acip production of kochujang meju were negligible. However, pH of doenjang meju decreased from 6.29 to 5.88 and acidity increased from 0.08 to 0.23% as lactic acid. Protein in meju was found to be rapidly solubilized during the early stage of fermentation. Soluble protein cotents of kochujang meju after 7 days and 60 days were 8.23%, respectively. The doenjang mejus were 2.15% after 20 days and 5.72% after 60 days. Soluble suger content increased with the fermentation time. The soluble sugar content was higher in kochjang meju. Acidic protease was highly produced during meju fermentation. $\alpha$-Amylase and $\beta$-amylase were detected in the kochujang meju, of which glutinous rice consisted, but negligible in doenjang meju. Lipase was detected in kochujang meju, but was, negligible in doenjang meju. Microbial population increased drastically after 7 days of fermentation in kochujang meju and 20 days of fermentation in doenjang meju.

• 한국식품영양과학회지
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• 제20권2호
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• pp.148-155
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• 1991

Lipid oxidation and browning during fermentation of domestic Meju and Doenjang were examined in order to elucidate the antioxidative effects of browning products and phenol compounds from Meju and Doenjang. Peroxide values of lipids from Meju were detectable and slightly increased until 3 weeks of fermentation, but started to be decreased after 3 weeks of fermentation and notdetectable after 6 weeks. Peroxides were not detected in Doenjang during the whole fermentation, but started to be decreased after 3 weeks of period of 22 weeks fermentation. Carbonyl value were increased during the whole period of Meju fermentation, but started to be decreased at the early stage of Doenjang fermentation. Hydrophilic fraction of browning products from Meju was much higher than lipophilic fraction and the former fraction was dramatically increased at the early stage of the fermentation. But the both fractions maintained high values during Doenjang fermentation. Hydrophilic browning products and phenol and phenol compound in Meju showed strong antioxidative against linoleic acid.

• Journal of Microbiology and Biotechnology
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• 제34권4호
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• pp.863-870
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• 2024

Meju, a fermented soybean brick, is a key component in soybean foods like doenjang and ganjang, harboring a variety of microorganisms, including bacteria and fungi. These microorganisms significantly contribute to the nutritional and sensory characteristics of doenjang and ganjang. Amplicon-based next-generation sequencing was applied to investigate how the microbial communities of meju fermented at low and high temperatures differ and how this variation affects the microbial communities of doenjang, a subsequently fermented soybean food. Our metagenomic data showed distinct patterns depending on the fermentation temperature. The microbial abundance in the bacterial community was increased under both temperatures during the fermentation of meju and doenjang. Weissella was the most abundant genus before the fermentation of meju, however, it was replaced by Bacillus at high temperature-fermented meju and lactic acid bacteria such as Weissella and Latilactobacillus at low temperature-fermented meju. Leuconostoc, Logiolactobacillus, and Tetragenococcus gradually took over the dominant role during the fermentation process of doenjang, replacing the previous dominant microorganisms. Mucor was dominant in the fungal community before and after meju fermentation, whereas Debaryomyces was dominant under both temperatures during doenjang fermentation. The dominant fungal genus of doenjang was not affected regardless of the fermentation temperature of meju. Strong correlations were shown for specific bacteria and fungi linked to specific fermentation temperatures. This study helps our understanding of meju fermentation process at different fermentation temperatures and highlights different bacteria and fungi associated with specific fermentation periods which may influence the nutritional and organoleptic properties of the final fermented soybean foods doenjang.

• Journal of Microbiology and Biotechnology
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• 제24권5호
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• pp.648-660
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• 2014

Doenjang, a traditional Korean fermented soybean paste, is made by mixing and ripening meju with high salt brine (approximately 18%). Meju is a naturally fermented soybean block prepared by soaking, steaming, and molding soybean. To understand living bacterial community migration and the roles of bacteria in the manufacturing process of doenjang, the diversity of culturable bacteria in meju and doenjang was examined using media supplemented with NaCl, and some physiological activities of predominant isolates were determined. Bacilli were the major bacteria involved throughout the entire manufacturing process from meju to doenjang; some of these bacteria might be present as spores during the doenjang ripening process. Bacillus siamensis was the most populous species of the genus, and Bacillus licheniformis exhibited sufficient salt tolerance to maintain its growth during doenjang ripening. Enterococcus faecalis and Enterococcus faecium, the major lactic acid bacteria (LAB) identified in this study, did not continue to grow under high NaCl conditions in doenjang. Enterococci and certain species of coagulase-negative staphylococci (CNS) were the predominant acid-producing bacteria in meju fermentation, whereas Tetragenococcus halophilus and CNS were the major acid-producing bacteria in doenjang fermentation. We conclude that bacilli, LAB, and CNS may be the major bacterial groups involved in meju fermentation and that these bacterial communities undergo a shift toward salt-tolerant bacilli, CNS, and T. halophilus during the doenjang fermentation process.

• 한국식품과학회지
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• 제31권6호
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• pp.1405-1409
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• 1999

본 연구는 콩, 메주, 된장에서의 isoflavones의 aglycones % 차이와 ${\beta}-glucosidase$의 활성을 살펴보기 위하여 수행되었다. Isoflavones 중 체내 이용률이 높은 aglycones %는 콩보다는 메주, 된장에서 높게 나타났다. 콩의 경우 유리 daidzein이 106 mg/kg, 총 dai-dzein은 406 mg/kg으로 aglycones 비율이 26.03%이었고 유리 genistein이 95 mg/kg, 총 genistein은 484 mg/kg으로 aglycones 비율이 19.49%이었으며 daidzein/genistein ratio는 0.85이었다. 메주는 유리 daidzein이 269 mg/kg, 총 daidzein은 433 mg/kg으로 aglycones 비율이 61.96%이었고 유리 genistein이 137 mg/kg, 총 genistein은 200 mg/kg으로 aglycones 비율이 68.52%이었으며 daidzein/genistein ratio는 2.16였다. 된장은 유리 daidzein이 578 mg/kg, 총 daidzein은 538 mg/kg으로 aglycones 비율이 107.68%이었고 유리 genistein이 455 mg/kg, 총 genistein은 538 mg/kg으로 aglycones 비율이 85.26%이었으며 daidzein/genistein ratio는 1.00이었다. ${\beta}-glucosidase$의 활성은 콩(5.65 units/mg protein), 메주(2.04 units/mg protein), 된장(0.69 units/mg protein)의 순이었다. pH변화에 따른 ${\beta}-glucosidase$ 활성 변화를 조사한 결과 콩은 pH 6.5, 메주와 된장은 pH 7.0에서 최대 활성을 나타냈다. 온도에 있어서는 $50^{\circ}C$에서 최대 활성을 보였다.

• 한국미생물·생명공학회지
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• 제24권2호
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• pp.247-253
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• 1996

Changes in microorganisms, enzyme activities and major components of two types of Doenjang prepared with spring Meju and autumn Meju and Kochujang were investigated during 4 months of fermentation. The viable cell counts of aerobic bacteria in Doenjang and Kochujang were increased up to 60 days of fermentation, but viable cell counts of anaerobic bacteria did not show remarkable changes during fermentation. Viable cell count of yeast showed a rapid increase up to 15 days of fermentation in Doenjang and 60 days in Kochujang. It was found that $\alpha$-amylase activity of autumn Meju Doenjang and glucoamylase activity of Kochujang were higher than the other. Acidic and neutral protease showed the highest activity during 15-30 days of fermentation. The pH of Doenjang was increased up to pH 7.0 until 60 days of fermentation, but pH of Kochujang gradually decreased during fermentation. Moisture content of spring Meju Doenjang and Kochujang decreased to 40% during ferme- ntation and reducing sugar content of Kochujang increased up to 15 days of fermentation, but decreased after that.

• 한국식품영양과학회지
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• 제23권5호
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• pp.792-798
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• 1994

In order to investigate the antioxidant activity of phenolic compounds contained in domestic Meju and Doenjang , the methanolic extract from defatted Meju and Doenjang was fractionated into the phenolic acid and the isoflavone fractions by alumina column and polyamide-6 column chromatography, respectively. Both phenolic acid and isoflavone fractions exhibited an identical antioxidative effect against the oxidation of linoleic acid. GC analysis revealed that the phenolic acid fractio contained vanillic , chlorogenic ,p-coumalic , ferulic, and caffeine acid. The content of caffic acid was greater than 70% in the phenolic acid fraction and the content of vanillic and chlorogenic acids were disappeared during fermentation, and thus, the facts are thought to be reasons for the low antioxidant activity of the phenolic aicd fraction from Doenjang. Similarly, the isoflavone fraction cotained daidzin, glycitin-65-0 glucosider and genistin and their aglycons such as daidzein, glyciten and genistein. The content of daidzin and genistin in Meju dramatically decreased at the early stage of fermentation ,whereas the content of daidzein an dgenistein rather increased ; however, these change in isoflavone contents did not affect the antioxidant activity of isoflavone fractions.

• 한국식품조리과학회지
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• 제25권1호
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• pp.90-97
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• 2009

Changes in the quality characteristics of doenjang prepared with a meju containing components of Acanthopanax senticosus, Angelica gigas and Corni fructus during storage were evaluated. Three types of doenjang produced using each of these components showed lower Hunter's L and a values than the values of the control during the initial stage of storage: however, these values were similar to those of the control after 60 days of storage. Doenjang containing A. gigas showed a similar degree of browning to that of the control during the early stage of storage, while the degree of browning observed in the other samples was much higher than that og the control during this period. Despite these initial differences, the browning in all samples became similar after extended storage. The level of acidity increased gradually for up to 60 days, after which it decreased slightly. The pH of all treatments decreased with storage time. The amino-N contents of all types of doenjang increased gradually, reaching peak values after 60 days. Doenjang with A. senticosus and A. gigas had a strong characteristic flavor that reduced the native flavor of doenjang. Doenjang with C. fructus showed a similar overall palatability to that of the control.

• 한국미생물·생명공학회지
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• 제47권3호
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• pp.354-358
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• 2019

메주를 염수에 침지하여 된장을 만드는 과정 동안 진균의 군집 변화와 재료가 된 메주와 천일염의 균총 천이를 확인하고자 진균의 ITS (internal transcribed spacer) 유전자 서열을 기반으로 하는 pyrosequencing을 통해 미생물 군집을 확인하였다. 된장의 주요 원료인 메주는 Botrytis spp.(57.94%)와 Dothiorella samentorum (24.08%)가 우점종으로 확인되었다. 천일염은 확인되지 않은 종들이(70.13%) 검출되었고, 그 외 종들은 적은 비율로 다양하게 검출되었다. 된장은 진균 중 곰팡이가 아닌 효모인 Candida versatilis(92.62%)가 가장 높은 우점진균으로 확인되었다. 메주의 저염은 곰팡이 생육이 용이 했고, 천일염은 고세균 또는 호염진균, 된장은 고염 효모의 생존에 용이했던 것으로 판단된다. 메주와 천일염의 우점진균이 된장의 균총에 직접적인 영향을 미치지 못하는 것으로 판단된다.

• Applied Biological Chemistry
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• 제37권4호
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• pp.266-271
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• 1994

쌀을 된장제조의 원료로 사용하되 된장 본래의 맛과 향을 지닌 된장 제조를 위해 대체원료로 사용되는 쌀의 배합비를 달리하고, 메주 및 고오지를 각각 이용하여 제조한 메주 된장 및 고오지 된장의 이화학적 특성 및 관능품위를 조사한 결과는 다음과 같았다. 쌀의 배합비에 따른 각 종류별 된장의 수분 및 염도에서 유의적인 차이는 볼 수 없었다. 단백용 해율의 경우 고오지 된장이 $32{\sim}50%$인 반면에 메주 된장은 $14{\sim}24%$로 비교적 낮았으며, 된장의 제조방법에 관계없이 쌀의 배합 비율이 높을수록 단백용해율이 낮았다. 단백분해율 및 포르몰태질소 함량도 단백용해율과 유사한 경향을 보였다. 고오지 된장의 pH는 $5.0{\sim}5.2$인 반면에 메주 된장은 $pH\;4.6{\sim}4.8$로 고오지 된장에 비해 전반적으로 낮았으며, 쌀의 배합비가 높을수록 고오지 된장의 pH는 높아졌으나 메주 된장의 pH는 낮아지는 경향을 보였다. 환원당의 경우 고오지 된장이 $19{\sim}21%$, 메주 된장이 $5{\sim}6%$로 쌀의 배합비가 높을수록 환원당의 양도 높았다. 한편, 쌀을 대체원료로 사용한 된장의 관능품위를 조사한 결과 전반적으로 고오지 된장의 점수가 메주 된장에 비해 높았으며, 고오지 된장 제조시의 쌀의 배합비는 20%가 가장 적합하였다.