• 한국식품조리과학회지
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• 제21권1호
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• pp.1-11
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• 2005

The application of Dongchimi liquid into Naengmyon broth for the improved eating quality of Naengmyon was scientifically explored by reviewing the quality properties of the product. Primarily, the optimum fermentation conditions for Dongchimi from which the liquid portion was extracted were pursued and the optimum mixing ratio was sought on the basis of sensory and microbiological properties of the product. The liquid portions which had been periodically extracted from Dongchimi at intervals of two or five days during fermentation at $10^{\circ}C$ were added to Naengmyon broth. The treatments were prepared with three levels, namely, basic broth only('A') and the ratios of 3:7(v/v, 'B') and 5:5(v/v, 'C') of Dongchimi liquid and basic broth, respectively. According to assessments of Dongchimi liquid on taste and intensity based on sensory analyses, the organoleptic factors such as color, smell, sour taste, carbonated taste, and overall acceptability were given higher values from day 11 to day 17 in all items. As for the assessment of Dongchimi liquid on intensity, color, sour odor, moldy odor, and carbonated taste have shown the increasing scores during with high intensities while those for clearness has stayed low. Most of the phenomena observed from the Naengmyon broth substituted with $30\%$ (Treatment 'A') and $50\%$ (Treatment 'B') of Dongchimi liquids with different storage periods ensued much of the previous fermentation pattern of Dongchimi itself. Organoleptic assessment on taste and its intensity showed that better(the best) scores could be obtained at between day 16$\~$25(17) and 13$\~$20(15) for Treatments A and B, respectively. The intensity scores of taste for color, smell, carbonated taste, sour taste, and mouthfeel were increased while those for clearness, palatability, and meaty ones were decreased with lapse of fermentation. The numbers of total cell and lactic acid bacterial counts of Dongchimi has increased until day 13 and then decreased in the later stages. Total cell count and lactic acid bacterial counts of Naengmyon broth also increased until the 13th day and then they began to decrease. It was also proven that slightly over-ripened Dongchimi liquid was more preferable for adding into Naengmyon broth. Granting the optimum ripening period of Dongchimi liquid itself to be 13 days, both Treatment A and Treatment B were evenly favored using Dongchimi liquids slightly over-ripened at days 13 to 17. However, Treatment A was more favored than Treatment B when Dongchimi liquid over-ripened for 20 to 26 days was used.

• 한국미생물·생명공학회지
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• 제26권4호
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• pp.369-372
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• 1998

Microbial insecticide formulations were prepared by liquid and semi-solid fermentations using Bacillus thuringiensis subsp. kurstaki, HL-106 (BTK-HL106), B. thuringiensis subsp. israelensis HL-63 (BTI-HL63) and B. sphaericus 1593 (BS-1593) strains. The liquid fermentation medium contained molasses 2%, dextrose 1.5%, peptone 2%, D-xylose 0.025%, CaCl$_2$ 0.1%, K$_2$HPO$_4$ 0.1%, KH$_2$PO$_4$ 0.1%, MgSO$_4$$.$7H$_2$O 0.03%, FeSO$_4$$.$7H$_2$O 0.002%, ZnSO$_4$$.$7H$_2$O 0.02%. The composition of the semi-solid fermentation medium was rice bran 45.2%, zeolite 31%, yeast powder 0.02%, corn powder 5%, dextrose 3%, lime 0.3%, NaCl 0.06%, CaCl$_2$ 0.02%, and H$_2$O 15.42%. Insecticide formulations produced in the liquid fermentation named BTK-HL106, BTI-HL63 and BS-1593 pesticides and those in the semi-solid fermentation were designated as BTK-HL106-1, BTI-HL63-1 and BS-1593-1 pesticides, respectively. The number of spore (endotoxin crystals) was 2.65${\times}$10$\^$9/ spores per $m\ell$ in the BTK-HL106 and 3.5${\times}$10$\^$10/ in the BTK-HL106-1 3.8${\times}$10$\^$9/ spores in the BTI-HL63 and 7.0${\times}$10$\^$10/ in the BTI-HL63-1, and 7.5${\times}$10$\^$9/ in the BS-1593 and 1.4${\times}$10$\^$10/ in the BS-1593-1. The spores in the BS-1593 formulation was produced two times more than the other formulations. The spores in the BTI-HL63-1 were contained twice than those in the BTK-HL106-1, and five times than those in the BS-1593-1. The results indicated that spore (endotoxin crystals) productions in the semi-solid fermentation increased about ten times than those in the liquid fermentations. $LC_{50}$s of the BTI-HL63 and BS-1593 were 4.5 $\mu\textrm{g}$, and those of the BTI-HL63-1 and BS-1593-1 were 1.5 $\mu\textrm{g}$. $LC_{50}$ of the BTK-HL106 was 1.5 mg and that of the BTK-HL106-1 was 0.9 mg. The $LC_{50}$s of the formulations in the semi-solid fermentations showed about two to three times higher than those in the liquid fermentations.

• 한국미생물·생명공학회지
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• 제39권4호
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• pp.357-363
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• 2011

고역가 액체종국 제조 및 배양기술을 개발하기 위해, Aspergillus 속의 곰팡이(A. oryzae, A. niger)를 이용한 밀기울 첨가율 별(0, 5, 10, 15 및 20%) 배지를 이용한 액체종국을 제조하여 이들의 품질 특성을 조사하였다. 액체종국의 일반성분 및 효소활성(glucoamylase, acidic protease)을 조사한 결과, 배지에 밀기울 첨가량이 많을수록 균사체량이 많아졌을 뿐만 아니라 산도, 아미노산도도 증가하는 것을 알 수 있었고 액체종국에 첨가하는 밀기울 농도가 달라짐에 따라 각 균주의 효소활성이 바뀌는 것을 알 수 있었다. 또한, 효소활성에 따른 최적 배양시간은 곰팡이 종류에 따라 차이가 있었고 A. oryzae와 A. niger 곰팡이의 액체종국 배양은 10~15% 밀기울을 첨가하여 48~72시간 배양하는 최적조건을 규명하였다. 기존에 사용되었던 고체종국과 비교하여 밀입국제조에 종국으로써 적합한지를 구명하고자 A. oryzae와 A. niger를 사용한 고체종국을 접종한 밀누룩을 대조구로 하여 밀기울 10% 액체배지로 만든 액체종국의 접종량 별(1, 3, 5, 10%) 밀누룩의 배양시간 별(0, 15, 20, 36, 38, 40 hrs) 및 이화학적 특성과 효소활성(${\alpha}$-amylase, glucoamylase, acidic protease)변화를 비교하였다. 결론적으로 시간과 인력등의 경제적 가치가 많이 투입되는 고체종국 보다는 누룩 제조시 액체종국을 사용하는 것이 여러 가지 측면에서도 유리 하다고 여겨진다.

• 한국식품과학회지
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• 제23권2호
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• pp.183-187
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• 1991

김치의 발효촉진과 억제효과를 검토하기 위하여 microwave에 의한 절임배추의 열처리, 효소 및 김치액의 첨가, 완충액과 몇 가지 무기염을 첨가하여 $25{\sim}35^{\circ}C$에서 발효하는 동안 pH의 변화를 측정하였다. 그 결과 순간 열처리와 amylase 및 celulase 첨가 단독으로는 김치발효 시간 단축에 뚜렷한 효과가 없었으나 이들을 병용하였을 때는 현저한 발효촉진 효과가 있었다. 김치액의 첨가는 pH 4.6의 것을 10%되게 첨가하고 발효시켰을 때 발효가 2배 정도 빨라졌고 맛과 냄새에서도 다른 pH의 김치액보다 좋았다. 완충액 중 phosphaste 완충액이, 무기염 중에서는 nitrite염, $Na_2HPO_4$가 김치발효를 현저히 억제시켜 김치 저장성 향상을 위한 첨가물로서의 가능성을 보여주었다.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2001년도 추계정기 학술발표회 초록집
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• pp.21-21
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• 2001

• 유기물자원화
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• 제27권4호
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• pp.61-70
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• 2019

본 연구는 농가에서 손쉽게 구할 수 있는 농축수산 부산물인 어분, 골분, 참깨박을 대상으로 액비 발효과정 중 이화학성 특성과 제조된 액비 처리에 따른 무 종자 발아 및 토마토 처리에 따른 작물 생육과 토양 환경에 미치는 영향을 검토하고자 수행하였다. 어분, 골분, 참깨박 액비 제조 시 발효기간 동안 액비의 pH는 발효가 진행될수록 골분 > 어분 > 참깨박 액비 순으로 높아졌으며 EC농도는 액비 3종 모두 30일까지 급격히 증가하다가 이후 변화가 적은 것으로 나타났다. 액비의 질소 함량은 발효가 진행될수록 모두 증가하였으며 어분 > 골분 > 참깨박 액비 순으로 높았다. 인산 함량도 발효가 진행될수록 증가하였으며 참깨박 액비가 1.0 % 로 가장 높게 나타났다. 액비 종류별 희석배수에 따른 무 종자의 발아율과 발아지수 결과는 어분과 참깨박 액비 10배 희석 처리구를 제외하고는 모든 처리구에서 95 % 이상의 발아율을 나타냈으며 발아지수는 액비가 희석될수록 증가하는 경향을 나타냈다. 액비 처리에 따른 토마토 생육 및 수량은 액비 처리간에 유의한 차이는 없었으며 화학비료 처리구에 비해 토양 중 유기물 함량, 미생물 밀도 그리고 미생물체량이 높게 나타났다. 이러한 결과로부터 유기자원을 활용한 액비 특성은 재료에 따라 차이가 있으며 유기농작물 재배 시 액비 시용으로 양분관리가 가능할 것으로 판단되었다.

• Journal of Microbiology and Biotechnology
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• 제34권3호
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• pp.654-662
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• 2024

To investigate the effect of the predominant fungal species from Korean traditional meju and doenjang on soybean fermentation, the enzymatic activity and amino acid production of twenty-two fungal strains were assessed through solid- and liquid-state soybean fermentation. Enzymatic activity analyses of solid-state fermented soybeans revealed different enzyme activities involving protease, leucine aminopeptidase (LAP), carboxypeptidase (CaP), glutaminase, γ-glutamyl transferase (GGT), and amylase, depending on the fungal species. These enzymatic activities significantly affected the amino acid profile throughout liquid-state fermentation. Strains belonging to Mucoromycota, including Lichtheimia, Mucor, Rhizomucor, and Rhizopus, produced smaller amounts of total amino acids and umami-producing amino acids, such as glutamic acid and aspartic acid, than strains belonging to Aspergillus subgenus circumdati. The genera Penicillium and Scopulariopsis produced large amounts of total amino acids and glutamic acid, suggesting that these genera play an essential role in producing umami and kokumi tastes in fermented soybean products. Strains belonging to Aspergillus subgenus circumdati, including A. oryzae, showed the highest amino acid content, including glutamic acid, suggesting the potential benefits of A. oryzae as a starter for soybean fermentation. This study showed the potential of traditional meju strains as starters for soybean fermentation. However, further analysis of processes such as the production of G-peptide for kokumi taste and volatile compounds for flavor and safety is needed.

• Journal of Applied Biological Chemistry
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• 제55권3호
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• pp.149-156
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• 2012

The effects of solvent type and concentration, solid/liquid ratio, extraction time and repeated extraction on recovery of keratinase from solid-state fermentation (SSF) of chicken feather by a local Streptomyces sp. NRC 13S were investigated in order to establish the experimental conditions for keratinase yield. Among solvents tested, 0.5% (v/v) glycerol was the best. Box-Behnken design was used to investigate the effect of relevant variables on keratinase recovery. The factors investigated were solid/liquid ratio (1:1.66-1:6.66 g/mL), glycerol concentration (0.5-5% v/v) and repeated extraction (1-5 cycle). The results showed that the maximum recovery of keratinase (6933.3 U/gfs) was obtained using 0.5 (v/v) glycerol as extracting solvent, in a solid/liquid ratio of 1:5 and three extraction cycles.

• 한국식품영양과학회지
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• 제25권3호
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• pp.513-518
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• 1996

In order to investigate the characteristics of alcohol fermentation by Saccharomyces cerevisiae, compositions and free sugar content of dried riped pumpkin powder were determined. The proximate compositions of ripe pumpkin powder were as follows: moisture 11.98%, total sugar 62.18%(dried weight basis 70.64%), protein 13.38%, lipid 0.85%, fiber 7.07% and ash 4.54%. The compositions of free sugar in well ripe pumpkin were: glucese 85.36mg/g, fructose 40.68mg/g, sucrose 68.25mg/g, lactose 18.60mg/g and maltose 3.82mg/g. The optimum conditions for alcohol fermentation by S. cerevisiae were as follows; incubation temperature of 3$0^{\circ}C$, initial pH of 6.0, ripe pumpkin powder concentration of 10% and cells inoculation of 1.3$\times$$10^{6}$ cells/ml liquid medium. Ethanol production under the optimum conditions was 5.95g/100g in liquid medium containing 10% ripe pumpkin powder after 4 days incubation.

• Journal of Microbiology and Biotechnology
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• 제23권8호
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• pp.1092-1098
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• 2013

Cassava constitutes an abundant substrate in tropical regions. The production of butanol in ABE fermentation by Clostridium beijerinckii BA101 using cassava flour (CF) was scaled-up to bioreactor level (5 L). Optimized fermentation conditions were applied; that is, $40^{\circ}C$, 60 g/l CF, and enzymatic pretreatment of the substrate. The batch fermentation profile presented an acidogenic phase for the first 24 h and a solventogenic phase afterwards. An average of 37.01 g/l ABE was produced after 83 h, with a productivity of 0.446 g/l/h. Butanol production was 25.71 g/l with a productivity of 0.310 g/l/h, high or similar to analogous batch processes described for other substrates. Solvent separation by different combinations of fractioned and azeotropic distillation and liquid-liquid separation were assessed to evaluate energetic and economic costs in downstream processing. Results suggest that the use of cassava as a substrate in ABE fermentation could be a cost-effective way of producing butanol in tropical regions.