• Journal of Microbiology and Biotechnology
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• 제4권3호
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• pp.215-221
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• 1994

Two strains of yeast (RA-74-2 and RA-912) showing superior fermenting ability at a high temperature were isolated from soils and wastewaters by an enrichment culture method. Based on the morphological and physiological charateristics, the two strains were identified as Saccharomyces cerevisiae and Kluyveromyces marxianus, respectively. RA-74-2 was able to grow upto $43^{\circ}C$ and sustain similar fermenting ability in the temperatures range from 30 to $40^{\circ}C$. In addition, the sugar- and ethanol-tolerance of RA-74-2 were 30% (w/v) glucose and 10% (v/v) ethanol, which appeared to be higher than those of nine other industrial yeast strains currently being used in the alcohol factories. The thermotolerant ethanol fermenting yeast RA-912 showed identical growth in the temperatures range from 35 to $45^{\circ}C$ and was resistant to various heavy metals. The quality and quantity of byproducts of the isolated yeast strains in fermentation broth after fermentation at $40^{\circ}C$ and $45^{\circ}C$ were similiar with those obtained at $30^{\circ}C$. These results show that RA-74-2 can be adopted for the ethanol fermentation process where the expenses for cooling system is significant, and suggest that RA-912 may be applied in either SSF(simultaneous saccharification and fermentation) or Flash-fermentation process and RA-912 may be used as a gene donor for the development of thermotolerant ethanol-fermenting yeasts.

• Journal of the Korean Wood Science and Technology
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• 제36권6호
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• pp.147-158
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• 2008

본 연구는 시멘트 블록조 발효상을 축조하고, 산림 및 농산 폐바이오매스의 발효 특성을 구명하기 위하여 수행되었다. 활엽수(신갈나무가 중심이 되는 활잡목)톱밥, 침엽수(낙엽송)톱밥, 낙엽류(소나무 및 플라타너스 낙엽), 볏짚, 산야초류 등 5종의 발효재료를 사용, 발효첨가제로서 요소, 발효용 부숙비료, 석회 등을 첨가하였고, 전체의 함수율을 55~60%가 되도록 조절하여 발효시켰으며, 궁극적으로 최대 발효열 효율을 얻기 위한 재료의 배합비, 최적수분함량 등을 검토하였다. 발열온도는 활엽수톱밥(100%)가 가장 좋았고 침 활엽수톱밥(50:50)구도 비교적 좋은 편이었다. 발열온도가 가장 높았던 활엽수톱밥 단독의 경우, 최고온도 $60{\sim}90^{\circ}C$, 최저온도 $40^{\circ}C$전후, 평균온도 $50{\sim}60^{\circ}C$의 범위를 20~30일간 유지하였으며, 이 때 최적 배합비율은 발효재료 1 톤에 대하여 요소 15 kg, 발효용 부숙비료 20 kg, 석회 10 kg, 함수율 55%이었다. 최적발효조건에서 온수탱크의 수온을 측정한 결과, 활엽수톱밥과 산야초를 50 : 50으로 혼합한 경우, 측정부위에 따라 상당한 편차를 보였으며, 발효상 중부 및 상부의 온도가 대체적으로 높았고, 하부층의 온도가 낮았다. 발열온도는 최고 $65^{\circ}C$, 최저 $40^{\circ}C$ 전후, 평균온도 $60^{\circ}C$였으며, 온수탱크의 온도를 45일간 측정한 결과, $30{\sim}45^{\circ}C$ 범위를 나타냈으며 전 기간을 통하여 거의 유사한 결과를 보여주고 있다. 탱크출구의 수온은 $33{\sim}48^{\circ}C$ 범위로 탱크온도보다 약간 높았다. 본 실험에서 개발된 열교환기(HX-helical type)를 사용한 경우, $50{\sim}60^{\circ}C$의 발효열을 최대 3개월정도 이용 가능하였다.

• 현장농수산연구지
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• 제10권1호
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• pp.169-181
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• 2008

The purpose of this study was to produce Pleurotus ostreatus using fermenter with bag cultivation. These results are as follows. 1. While mushroom composts were being fermented in a fermenter, the physical property of the fermented composts was getting better when there isn't any screw or revolving flies in the fermenter and the strength of pressing the composts was getting less. 2. The composts were fermented well as slaked lime of 1% density added to the composts. 3. According to the result of examining our fermenting ways, composts were in the best condition after being fermented for 48 hours since the temperature in a fermenter has come to 60℃, which could be reached by heating the fermenter by 40℃ after putting compost materials and water into it. 4. The good condition of fermenting could be maintained by controlling the speed of revolving flies, therefore the speed be down when the temperature is above 60℃ and up bellow 60℃. 5. Since the composts had been added with 1.5~2% of cottonseed meal or rice bran, the fermented composts were in good condition and also the quantity and quality of the mushroom produced on the fermented composts were satisfied. 6. There were needed 7 hours of labour for 3days from the first day of putting composts into a fermenter for fermenting 3.5M/T(10,000~12,000bags of 750~800g per bag) of composts to the third day of finishing the fermenting work, and also the cost was 112,066￦(130$) including 52,066￦(60$) of electric charge and fuel expense.

• 한국의류산업학회지
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• 제15권4호
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• pp.635-641
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• 2013

This study examined the dye-properties of natural fabrics dyed with Coptis chinensis and Curcuma longa root fermented with fungi. The optimum culture conditions for the fermentation of microorganisms, the relationship between natural dye color and fermentation conditions were investigated. Two different medical herbs (ground to 80-100 mesh in size) were used as a natural dyeing source. Phellinus linteus (P. linteus), which can grow in different media, such as Agarmedium (only agar containing medium), maltose extract agar (MA) and potato dextrose extract agar (PDA) culture media, were isolated from the medium. P. linteus was confirmed to be the optimum microorganism for the fermentation of Coptis chinensis and Curcuma longa, and the MA medium was confirmed to be the best for culturing. When using the microorganism as the fermenting agent, $32^{\circ}C$ was found to be the optimum fermenting temperature for both natural colorants. Regarding the dyeing property of the fermented natural dye, silk was dyed quite darkly in an appearance by naked eye estimation and the K/S value in the color strength of silk reached a high level of 16 after the fermenting process. The washing fastness of dyed silk after treatment washing was reduced from 4 to under4 and indicates that dyed silk with fermented plant was not unsubstantial. The light fastness was 1 to 2, showing intended to maintain due to the fermentation process.

• Food Science and Biotechnology
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• 제16권4호
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• pp.526-530
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• 2007

The objective of this study was to establish the optimum alcohol fermenting conditions for the processing of kiwi wine and vinegar products. Six yeast strains were examined for their alcohol production from kiwi at $30^{\circ}C$ for 72 hr with continuous shaking at 100 rpm. Under these conditions, Saccharomyces kluyveri DJ97 produced the highest alcohol content of 10.2%. As the fermentation time extended to 96 hr, the alcohol content reached a maximum of 12.75%. The optimum alcohol fermenting conditions for kiwi fruit were accomplished when kiwi was added to an equal amount of water, inoculated with S. kluyveri DJ97 and fermented at $30^{\circ}C$ for 96 hr with continuous shaking. The content of soluble solids decreased as the alcohol concentration increased, whereas little change was observed in the pH and titratable acidity during the low temperature aging process. Other alcoholic compounds, such as methanol, isopropanol, n-propanol, isobutanol, and isoamylalcohol, tended to increase as fermentation progressed.

• 유기물자원화
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• 제6권2호
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• pp.95-112
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• 1998

186종의 후보미생물을 대상으로 우수발효(소멸)균 선발시험을 실시한 결과, Rhizopus sp., Galactomyecs sp., Pichia sp., Hyphopichia sp.로 구성되는 4종의 발효균을 선발하였다. 이들 발효균을 이용한 발효(소멸)공정 시험결과, 내용적 50L의 발효조에 대해서, BIO-CHIP Volume 25-30L, BIO CHIP입도 2.0-6.0mm, 송풍량 200-280L/min, 교반강도 24 rpm, 온도 $30-45^{\circ}C$가 최저 발효조건인 것으로 나타났으며, 이러한 조건에서 1일 1kg의 음식물을 30일간 투입하면서 소멸기를 가동한 결과, 93%의 소멸율을 나타내었다. 소멸기 배출물의 재활용 가치를 평가하기 위하여, 발아율 시험을 실시한 결과, 배출물을 적절하게 희석하여 사용하면, 퇴비로서의 가치가 매우 양호한 것으로 나타났다.

• Journal of Microbiology and Biotechnology
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• 제26권4호
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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.

• 한국축산식품학회지
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• 제38권1호
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• pp.189-202
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• 2018

This study was conducted to evaluate the effects of fermenting temperature on the applicability of Lactobacillus plantarum for production of fermented sausages as starter cultures, and its applicable efficiency was also compared with those inoculated with commercial starter culture or non-inoculated control. The L. plantarum isolated from a naturally-fermented meat, identified by 16S rDNA sequencing and again identified by de novo Assembly Analysis method was used as a starter culture. Six treatments: 3 with L. plantarum at different fermenting temperatures (20, 25 and $30^{\circ}C$), and other 3 treatments (1 with commercial starter culture, 1 with its mixture with L. plantarum and 1 non-inoculated control) fermented under the same conditions ($25^{\circ}C$) were prepared. Results revealed that the fermenting temperature considerably affected the pH change in samples added with L. plantarum; the highest pH drop rate (1.57 unit) was obtained on the samples fermented at $30^{\circ}C$, followed by those at $25^{\circ}C$ (1.3 unit) and $20^{\circ}C$ (0.99 unit) after 4 days fermentation. Increasing the temperature up to $30^{\circ}C$ resulted in significantly lower spoilage bacteria count (5.15 log CFU/g) and lipid oxidation level in the products inoculated with L. plantarum. The sensory analysis also showed that the samples added with L. plantarum at $30^{\circ}C$ had significantly higher odor, taste and acceptability scores than those fermented at lower temperatures. Under the same processing condition, although the L. plantarum showed slightly lower acidification than the commercial starter culture, however, it significantly improved the eating quality of the product.

• 대한가정학회지
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• 제8권1호
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• pp.100-119
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• 1970

In finding an improved and generalized method of making Jung-pyun, a type of scientific experimental cookey has been attempted with the use of yeast in place of Korean native rice wine named "Takju" The result is shown as follows; 1. Starta prepared with yeast and rice powder was mixed again with fresh rice powder as fermenting and aging agents in Jung-pyum making. 2. Recommendable methods of starta making are shown as follows; a. Recipe Rice powder--Certain amount Yeast--1% Sugar--10% Water--65%(by volume) b. Temperature and Time of Fermentation Temperature--30$^{\circ}C$ Time--20 hrs. 3. Recommendable method of dough making are shown as follows; a. Recipe Starta--Certain amount Rice powder--Two times the starta(2-3 times) Sugar--10% Water--50%(by volume) b. Temperature and Time of Aging Temperature--35$^{\circ}C$ Time--3 hrs. (3-4 hrs) 4. Steaming Time 25-30 min.

• 한국미생물·생명공학회지
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• 제14권5호
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• pp.365-369
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• 1986

새로운 alcohol발효성 효모 균주 개발을 목적으로 S. diastaticus 와 C. tropicalis간의 세포 융합을 하여 얻은 fusant의 성질에 대해서는 제3보$^{(10)}$에서 발표한 바이다. 본 보에서 는 fusant의 glucoamylase와 pullulanase activity와 glucoamylase의 성질 및 발효력을 조사하였다. glucoamylase activity는 parent보다 fusant가 1.5배 높은 활성을 나타내었고 pullulanase activity 역시 두배의 높은 활성을 나타내었다. glucoamylase의 성질을 조사한 바 온도, pH에서 비슷한 경향을 나타내었으며 발효력을 조사하기 위하여 정치법에서는 기질을 soluble starch로 한 것 보다 liquefied potato starch에서 alcohol 생성력이 2배 증가되었으며 발효력 또한 더 나았다. 15% 액화한 potato starch를 기질로하여 jar-fermenter에서 발효시켰을 때 당화율 94%에서 생성된 alcohol이 7.8% (v/v)이고 소비된 당에 대한 발효율은 78%였다.