• Food Science and Biotechnology
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• 제16권1호
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• pp.146-149
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• 2007

Dynamic rheological properties of hot pepper-soybean paste (HPSP) mixed with xanthan gum were evaluated at different gum concentrations (0.3, 0.6, and 0.9%) and fermentation times (12 and 24 week). Magnitudes of storage (G') and loss moduli (G") in the HPSP-xanthan gum mixture systems increased with an increase in frequency ($\omega$), while complex viscosity (${\eta}^*$) decreased. G' values were higher than the G" values over most of the frequency range (0.63-63 rad/sec), and were frequency-dependent. The dynamic moduli (G', G", and ${\eta}^*$) of the HPSP-xathan mixtures were lower than those of the control (0% gum). The differences between the dynamic moduli values at 12-week and 24-week fermentation decreased with increasing gum concentration, showing that xanthan gum can be used to stabilize and improve the viscoelastic rheological properties of HPSP. The G' value of the HPSP-xathan mixtures increased with an increase in gum concentration from 0.3 to 0.9%, whereas the G" decreased. The ability of xanthan gum to increase the elastic properties in the HPSP-xanthan mixture systems seemed to be the result of the incompatibility phenomena existing between xanthan gum and glutinous rice starch.

• 미생물학회지
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• 제54권4호
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• pp.453-455
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• 2018

된장으로부터 콩발효 종균후보 Bacillus licheniformis 0DA23-1가 분리되었다. 0DA23-1 균주는 GC 함량 45.96%, 약 4.4 Mb 크기의 단일 chromosome을 보유하고 있었고, 식중독균 Bacillus cereus 및 Staphylococcus aureus가 보유한 위해성 유전자는 유전체로부터 확인되지 않았다. 또한, 8종의 항생물질(chloramphenicol, clindamycin, erythromycin, gentamicin, kanamycin, streptomycin, tetracycline, vancomycin) 저항성 및 혈청분해 활성, 바이오필름 생성 관련 유전자도 확인되지 않았다.

• 한국식품과학회지
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• 제44권1호
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• pp.69-75
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• 2012

대두의 발아시간이 발아대두 청국장의 품질특성에 미치는 영향을 조사하기 위하여 청국장의 발효기간 중 아미노태질소 및 isoflavone 함량 등의 이화학적 특성과 amylase 및 protease 등 효소활성을 비교하였다. 전통 청국장에서 분리한 균주 중 이취가 상대적으로 적고, 점질물 생성량이 많은 B. subtilis SCD 115035 균주를 선발하여 청국장 제조에 사용하였다. 청국장의 pH는 발효 초기 pH 6.68-6.74에서 발효가 진행됨에 따라 점차 증가하여 발효 48시간에 pH 7.47-7.68을 나타냈다. 청국장의 점질물 함량은 발효 48시간에 발아 12시간 처리구에서 13.22%로 가장 높았으며, 대두의 발아시간이 증가함에 따라 점질물 함량은 감소하였다. 산성 protease 활성은 발아 0시간 처리구에서 발효 72시간에 0.323 unit/mL로 가장 높았다. 산성 및 중성 protease 활성은 비발아대두로 제조한 청국장에서 발아대두로 제조한 청국장보다 높게 나타났다. ${\alpha}$-Amylase와 ${\beta}$-amylase 활성은 발아 시간 및 발효 시간에 따라 큰 차이를 보이지 않았다. 비발아대두로 제조한 청국장의 아미노태질소 함량이 발효 48시간에 436.93 mg%로 가장 높았으며, 그 함량은 발아 12시간 처리구와 비슷하였다. 발아 36시간 처리구의 총 isoflavone 함량은 발효 72시간에 $839.86{\pm}8.24{\mu}g/g$로서 가장 높았으며, 발효기간 동안 발아 0, 12, 24시간 처리구보다 높게 나타났고, 발아 0, 12, 24시간 처리구 사이에는 큰 차이가 없었다. 청국장을 제조하기 위하여 대두를 발아했을 때 점질물의 함량, protease 활성 및 아미노태 질소 함량은 대조구보다 감소하였으나 기능성 성분인 isoflavone 함량은 발아 36시간 처리구에서 가장 높은 것으로 나타났다.

• Journal of Microbiology and Biotechnology
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• 제27권11호
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• pp.1952-1960
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• 2017

Recently, soybean isoflavone aglycones (i.e., daidzein and genistein) and ${\gamma}-aminobutyric$ acid (GABA) have begun to receive considerable consumer attention owing to their potential as nutraceuticals. To produce these ingredients, multiple microorganisms and their enzymes are commonly used for catalysis in the nutraceutical industry. In this work, we introduce a novel fermentation process that uses whole-cell biocatalysis to accelerate GABA and isoflavone aglycone production in doenjang (a traditional Korean soybean paste). Microbial enzymes transform soybean isoflavone glycosides (i.e., daidzin and genistin) and monosodium glutamate into soybean isoflavone aglycones and GABA. Lactobacillus brevis GABA 100 and Aspergillus oryzae KACC 40250 significantly reduced the production time with the aid of a protease. The resulting levels of GABA and daidzein were higher, and genistein production resembled the levels in traditional doenjang fermented for over a year. Concentrations of GABA, daidzein, and genistein were measured as 7,162, 60, and $59{\mu}g/g$, respectively on the seventh day of fermentation. Our results demonstrate that the administration of whole-cell L. brevis GABA 100 and A. oryzae KACC 40250 paired with a protease treatment is an effective method to accelerate GABA, daidzein, and genistein production in doenjang.

• 미생물학회지
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• 제48권3호
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• pp.220-224
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• 2012

전통 장류 제품 내 유해한 biogenic amines 양을 감소하기 위해, 83종의 전통 장류에서 biogenic amines을 분해할 수 있는 5종의 균주들을 분리하였다. 이들 균주들을 histamine, tyramine, putrescine, cadaverine이 각각 5.3% 함유된 삶은 콩에 접종하여 10일 간 발효시킨 결과 biogenic amines 함량을 27-92% 수준으로 감소시켰다. 선발한 균주들의 형태 및 생화학적 특성, 16S rRNA 유전자 서열 해독 결과 5종의 균주들은 Bacillus subtilis 또는 B. amyloliquefaciens에 속했다. 이 선발 균주들을 사용함으로서 biogenic amines 수준을 제어하기 힘든 전통 장류의 제조에 이 선발 균주들의 사용은 이들 함량을 줄일 수 있는 효과적 방안이 될 수 있다.

• 한국미생물·생명공학회지
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• 제9권4호
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• pp.253-261
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• 1981

Fermented foods available in Korea may be classified into four groups, namely, fermented soybean products, fermented cereal products, fermented vegetable products, and fermented fishery products based on raw materials used. The representative fermented foods based on soybean are Kanjang(soysauce), Doenjang(fermented soybean pastes), and Kochujang(red pepper added-fermented soybean paste). Such fermented products are made using Meju(functioning as a starter and prepared by fermentation of steamed soybean mash) as an essential ingredient, and used widely as a soup base and/or in seasoning side-dishes for everyday meals year around. Excepting Sikhae, all fermented products based on rice and other cereal grains are of alcoholic nature. Takju (Makgeolli) used to be made using rice as the major raw material, however, mainly due to the shortage of rice in recent years, other cereals, such as, barely, corn, and wheat flours are also used to replace rice today. Owing to such changes in the raw materials. the popularity of Takju has been somewhat reduced, yet it is still widely consumed in rural areas. Although Chungju is a popular rice wine with superior qualify over Takju, the amount consumed is considerably limited. The highest qualify rice wine, Bupju, in particular, is made by a low temperature fermentation using glutinous rice. Kimchi is an unique fermented vegetable product of long tradition in Korea. Although it was for consumption mainly in winter season serving as a source of vitamins, today it is widely used throughout the year. Except Kkakdugi and Dongchimi, all of the fermented vegetable products contain salted Korean cabbage as an essential item, while they abound in varieties depending on material composition and methods of processing, and also on seasons and localities Next to Kimchi in this category is Kkakdugi made of raddish in popularity and quantity consumed. The four groups of fermented food products described above are reviewed in some detail and evaluated in terms of their nutritional significances, processes and microorganisms involved. and their commercial potentials. Jeotkal (or Jeot) is a name given to all fermented products of fishery origin. A number of Jeot can be prepared by adding salt and allowing fermentation to the raw materials such as shrimp, anchovy octopus, clam, oyster, etc.

• 한국식품영양학회지
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• 제12권1호
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• pp.1-6
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• 1999

The strain isolated for making chungkuk-jang was Bacillus subtilis which formed sport with 98% ratio. Logarithmical culture was inoculated(1,000 CF/g) to the steamed soybeans and at th optimum fer-mentation conditions(4$0^{\circ}C$, RH 90%) fermentation progressed very rapidly and synchronously. Fermen-tation time was 24 hours on the optimum fermentation conditions. During activated fermentation chun-gkuk-jang's aroma and flavor created. After finishing the fermentation the spore forming ratio was 95% and replenishment was not occured easily during aging at the below 5$^{\circ}C$.

• Preventive Nutrition and Food Science
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• 제14권2호
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• pp.134-141
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• 2009

The changes in components and biological activities of doenjang samples prepared with black soybeans and fermented with Bacillus subtilis SCB were investigated. The amino nitrogen (A-N) contents of samples increased with increasing black soybean content. A doenjang product made using a 1:1 ratio of soybeans-black soybeans showed a maximum level of genistein and daidzein isoflavones ($1111.6{\mu}g/g$) at 110 days of fermentation, along with decreasing contents of genistin and daidzin due to the conversion to aglycones. The black soybean-only doenjang sample showed higher protease activity, including caseinolytic and fibrinolytic enzyme activities, than the other samples, and had relatively higher polyphenol content and DPPH radical scavenging activity. Therefore, doenjang made with additions of black soybeans and fermented by B. subtilis SCB may have improved physiological properties, suggesting this to be a valuable method of preparation.

• 식품과학과 산업
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• 제53권2호
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• pp.183-199
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• 2020

Traditional food is the basis of Korean food, but in the process of industrialization, Japanese soybean fermented product making method became standardization process of Korean soybean fermented product as a factory type. As a result, traditional fermented food was pushed behind the industrialization. At present, there is anxiety in the development of the fermented soybean product industry due to the gap in management level between the manufacturers, the decrease in consumption of Jangryu due to changes in dietary life, and the negative image as high salt food. In order to overcome these problems and lead continuous growth, governmental industrial development policies such as traditional liquor and Kimchi are inevitably needed. By laying the legal and institutional foundation and making good use of it in industry, it will be the foundation for continuous development in the market where fierce competition is accelerated.

• Preventive Nutrition and Food Science
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• 제7권4호
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• pp.397-404
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• 2002

Soybean curd residue (SCR) was fermented by lactic acid bacteria, Lactobacillus rhamnosus LS and Entercoccus faecium LL, isolated from SCR. The pH, titratable acidify and viable cell counts were determined from the fermented SCR to evaluate the lactic acid production and growth of lactic acid bacteria. Optimal amounts of pretense enzyme and glucose, and ideal fermentation time for SCR fermentation were estimated by response surface methodology (RSM). Raw SCR fermented by indigenous microorganisms had 0.78 % titratable acidity, The acid production in SCR fermented by L. rhamnosus LS was greatly enhanced by the addition of glucose and lactose. However only glucose increased acid production by Ent. faecium LL. The proof test of SCR fermentation demonstrated that similar results for titratable acidity, tyrosine content and viable cell counts to that predicted could be obtained by the at optimized fermentation conditions. In the presence of 0.029 % (w/w) pretense enzyme and 0.9% (w/w) glucose, the SCR fermented by Ent. faecium LL showed 1.07% (w/v) of titratable acidity, 1.02 mg% tyrosine content and 2$\times$10$^{9}$ (cfu/g) of viable cell counts. With the SCR fortified with 0.033% pretense enzyme and 1.7% glucose, L. rhamnosus LS showed 1.8% (w/v) of titratable acidity, 0.92 mg% of tyrosine content and 2$\times$10$^{9}$ (cfu/g) of viable cell counts.