• 동아시아식생활학회지
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• 제20권5호
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• pp.743-750
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• 2010

The influence of various fermenting conditions using Saccharomyces cerevisiae, alone (Control, Single) and in combination with mixed lactic acid-producing bacteria (Combined 1, Mixed, Combined 2), including Bifidobacterium longum, Enterococcus faecium, and Lactobacillus acidophilus on flour sourdough preparation was examined. For the Combined 2 method, starters were incubated separately for 15 h, combined, and then further incubated for 10 h. Fermentation using Combined 2 improved the growth of mixed lactic acid-producing bacteria, but inhibited that of S. cerevisiae. This was also reflected in the extent of the pH reduction in sourdough produced in the Combined 2 step by these organisms. Among biochemical activities, $CO_2$ production and titratable acidity were increased by Combined 2, although the viable yeast counts were decreased. Aroma compounds in sourdough markedly varied according to fermentation conditions.

• 한국미생물·생명공학회지
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• 제20권4호
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• pp.430-436
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• 1992

수소 생성능이 있는 Clostridium butyricum과 이 균주의 대사산물을 이용하여 수소를 생성할 수 있는 광합성 세균의 혼합 배양에 의하여 수소 생성을 할 수 있는 양 균주의 혼합 배양 동력학적 연구를 수행하였다. 혐기성 Clostridia의 발효에서 생성되는 아세트산염과 부티르산염은 Rhodopseudomonas sphaeroides에 의해 이용되어 수소를 생성하게 되었고, 이들 양 균주를 혼합 배양한 결과 수소 생성을 저해하는 아세트산염과 부티르산염의 배지내 농도는 점차 감소하였다. 이들 두 균주의 혼합 배양에서의 균체의 혼합 비율, 혼합시기, 접종량을 조사함으로써 단독 배양시와 비교하면서 최적 조건을 조사하였고, 혼합시 균체량의 비율 Clostridium 속 세균1부에 대하여 Rhodopseudomonas 속 세균 6부의 비율로 혼합할 수 있음을 확인하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제19권4호
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• pp.533-540
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• 2006

In this study, the possibility of green tea waste (GTW) as a new ingredient of byproducts-mixed silage was investigated. Characteristics of GTW were low in dry matter (DM) content (20%), and high in crude protein (30 to 36%) and tannins (8.5%). The GTW was added to mixed silages composed of tofu cake, rice straw and rice bran that are locally available in Japan. In experiment 1, the effect of GTW addition to silage made from various patterns of byproducts mixture based on tofu cake was studied. In experiment 2, the effect of GTW addition and storage temperature on fermentation characteristics, nutrient contents and in vitro ruminal gas production of byproducts-mixed silages were examined. In experiment 1, GTW addition on tofu cake accelerated acetic, propionic and butyric acid accumulation in the silage. When rice straw was mixed with tofu cake, DM content was increased from 47 to 56%, lactic acid was the main acid and the pH was decreased below 4.2. In this case, GTW addition to those mixtures did not affect acid concentrations of the silage. In experiment 2, GTW addition to the byproducts mixture increased lactic acid concentration, decreased the pH and DM loss of the silages. In GTW treatments, tannin concentration was lower in the silage stored at $30^{\circ}C$ than $15^{\circ}C$. Addition of GTW into the silage also increased in vitro ruminal gas production. It was concluded that addition of GTW into byproducts-mixed silage enhanced lactic acid fermentation when there were insufficient materials for lactic acid production. Utilization of GTW as an ingredient in mixed silages would be effective in enhancing fermentation characteristics, lowering tannin content and in vitro ruminal gas production.

• 한국식품영양과학회지
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• 제27권5호
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• pp.858-863
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• 1998

The Mixed effect of Salvia miltiorrhiza and Glycyrrhiza uralensis(SG) on kimchi fermentation was investigated by measuring changes of physicochemical, icrobiological and sensory qualities of kimchi during fermentation. The pH of SG-added kimchi was a little higher than that of control during the fermentation. Titratable acidity, viable cell of total bacteria and lactic acid bacteria in mixed medicinal herbs(SG) added kimchi were changed more slowly than those in control. The inhibitory effect of the mixture on kimchi fermentation was increased as the concentration of the mixture was increased from 1% to 5%. Total bacteria and lactic acid bacteria of 3% and 5% SG-added kimchi reduced to 1.3~2.9 and 1.2~4.0 log10 cycle after 15 days fermentatin compared to control. The changes in texture of SG-added kimchi was a higher and sour taste of SG-containing kimchi excepts of 1% SG-added kimchi was more weak than that of control. Sensory score of flavor and overall acceptability did not show any significant difference between SG-added kimchi and control during fermentation. But SG-added kimchi decreased its sensory quality by 5% the other kimch.

• Biotechnology and Bioprocess Engineering:BBE
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• 제10권2호
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• pp.128-135
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• 2005

Mixed-mode hydrophobic/ionic matrices exhibit a salt-tolerant property for adsorbing target protein from high-ionic strength feedstock, which allows the application of undiluted feedstock via an expanded bed process. In the present work, a new type of mixed-mode adsorbent designed for expanded bed adsorption, Fastline $PRO^{\circledR}$, was challenged for the capture of nattokinase from the high ionic fermentation broth of Bacillus subtilis. Two important factors, pH and ion concentration, were investigated with regard to the performance of nattokinase ad-sorption. Under initial fermentation broth conditions (pH 6.6 and conductivity of 10 mS/cm) the adsorption capacity of nattokinase with Fastline PRO was high, with a maximum capacity of 5,350 U/mL adsorbent. The elution behaviors were investigated using packed bed adsorption experiments, which demonstrated that the effective desorption of nattokinase could be achieved by effecting a pH of 9.5. The biomass pulse response experiments were carried out in order to evaluate the biomass/adsorbent interactions between Bacillus subtilis cells and Fastline PRO, and to demonstrate a stable expanded bed in the feedstock containing Bacillus subtilis cells. Finally, an EBA process, utilizing mixed-mode Fastline PRO adsorbent, was optimized to capture nattokinase directly from the fermentation broth. The purification factor reached 12.3, thereby demonstrating the advantages of the mixed-mode EBA in enzyme separation.

• 한국식품저장유통학회지
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• 제18권1호
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• pp.91-97
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• 2011

상업적 복합균주와 효모를 sourdough starter로 사용하여V5가지의 시료를 다음과 같이 준비하였다. 제빵용 효모만을V사용한 control군, 상업용 복합균주를 사용한 LAB 1군, 상업용 복합균주와 효모로 각각 발효한 후 합친 LAB 2군, 상업용 복합균주와 효모를 함께 사용하여 발효한 LAB 3군, 상업용 복합균주와 효모를 사용하여 각각 발효하여 합친 후 다시 10시간 발효한 LAB 4군을 사용하여 제조한 발효식빵의 제빵특성은 다음과 같다. CrumbScan에 의한 영상분석의 결과로 LAB 4의 부피가 2,140 cc로 가장 큰 것으로 발효율이 가장 높았던 LAB 4의 부피가 가장 크게 나타났다. 기공의 조밀도는 부피가 가장 큰 LAB 4가 806로 가장 낮게 나타났고, 기공의 찌그러짐 정도는 기공의 조밀도가 가장 높았던 LAB 1이 1.56으로 가장 높은 것으로 나타났다. 껍질의 두께는 대조구가 가장 얇았고 LAB 4가 가장 두껍게 나타나 유의적인 차이를 보였다. Sourdough bread의 비용적의 측정결과는 발효율이 가장 높았던 LAB 4의 비용적은 5.14 mL/g으로 가장 높게 나타났다. Firmness 측정결과는 93.2 g인 대조구에 비해 LAB 2, LAB 3과 LAB 4에서의 firmness 측정치는 각각 113.67, 111.97, 113.50 g로 높게 나타났다. 관능검사 결과에서 식빵의 내부색은 전반적으로 밝게 평가되었으며, LAB 4의 기공이 가장 균일한 것으로 나타났고 촉감도 가장 부드러운 것으로 평가되었고, 전체적인 품질평가에서도 3.7을 나타내어 가장 선호하는 것으로 나타났다. 결과적으로 대부분의 평가항목에서 LAB 4로 만든 sourdough bread를 선호하는 것으로 나타났다.

• 한국식품위생안전성학회지
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• 제4권1호
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• pp.37-44
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• 1989

멸치를 물로 씻은 후 식염 10%, 15%, 20% 및 식염과 염화칼리 1:1 홈합염 10%를 각기 첨가하여 1~12주간 숙성할 때 불휘발성 아민의 함량과 미생물의 변화와 시중에 유통중인 멸치젓의 불휘발성아민 함량을 조사하였다. 불휘발성아민은 식염농도가 높을수록 생성량이 적었고 숙성기간별 생성량은 histamine의 경우 숙성 초기부터 증가하여 6주째에 식염 10%, 멸치젓이 657.8ppm으로 최고치를 나타낸 후 감소하기 시작하여 숙성 12주째는 식염 20%, 멸치젓이 210.8ppm으로 가장 적었고 혼합염 10% 멸치젓이 310.8ppm으로 가장 많이 생성되었다. Cadaverine과 putrescine은 숙성 8주째까지 생성량이 증가한 후 점차적으로 줄어들었고 tyramine은 숙성 10주째까지 RPthrwmd가한 뒤 숙성 12주째 현저히 감소하였다. 시중 유통품과 식염 함량이 비슷한 20% 멸치젓의 12주째 실험결과를 비교하면 시중 유통품의 불휘발성 아민 함량이 전반적으로 높게 나타났다. 미생물의 변화는 숙성 초기에는 Achromobacter 속, Aeromonas 속 및 Pseudomonas속이, 숙성 중기에는 Pediococcus속 , Microc....us 속 및 Lactobacillus 속이 많았으며 숙성 후기에는 Sacchromyces 속이 증가하였고 전 숙성기간 동안 미생물은 109주가 분리되었다.

• Animal Bioscience
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• 제37권1호
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• pp.84-94
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• 2024

Objective: The objective of this study was to investigate how cellulase or/and lactic acid bacteria (LAB) affected the fermentation characteristic and microbial community in wet brewer's grains (WBG) and corn stover (CS) mixed silage. Methods: The WBG was mixed thoroughly with the CS at 7:3 (w/w). Four treatment groups were studied: i) CON, no additives; ii) CEL, added cellulase (120 U/g fresh matter [FM]), iii) LAB, added LAB (2×10⁶ cfu/g FM), and iv) CLA, added cellulase (120 U/g FM) and LAB (2×10⁶ cfu/g FM). Results: All additive-treated groups showed higher fermentation quality over the 30 d ensiling period. As these groups exhibited higher (p<0.05) LAB counts and lactic acid (LA) content, along with lower pH value and ammonia-nitrogen (NH₃-N) content than the control. Specifically, cellulase-treated groups (CEL and CLA) showed lower (p<0.05) neutral detergent fiber and acid detergent fiber contents than other groups. All additives increased the abundance of beneficial bacteria (Firmicutes, Lactiplantibacillus, and Limosilactobacillus) while they decreased abundance of Proteobacteria and microbial diversity as well. Conclusion: The combined application of cellulase and LAB could effectively improve the fermentation quality and microbial community of the WBG and CS mixed silage.

• Journal of Microbiology and Biotechnology
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• 제24권5호
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• pp.629-638
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• 2014

This study describes an alternative mixed culture fermentation technology to anaerobically convert lignocellulosic biomass into butyric acid, a valuable product with wide application, without supplementary cellulolytic enzymes. Rice straw was soaked in 1% NaOH solution to increase digestibility. Among the tested pretreatment conditions, soaking rice straw at $50^{\circ}C$ for 72 h removed ~66% of the lignin, but retained ~84% of the cellulose and ~71% of the hemicellulose. By using an undefined cellulose-degrading butyrate-producing microbial community as butyric acid producer in batch fermentation, about 6 g/l of butyric acid was produced from the pretreated rice straw, which accounted for ~76% of the total volatile fatty acids. In the repeated-batch operation, the butyric acid production declined batch by batch, which was most possibly caused by the shift of microbial community structure monitored by denaturing gradient gel electrophoresis. In this study, batch operation was observed to be more suitable for butyric acid production.

• 한국식품영양과학회지
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• 제38권12호
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• pp.1811-1814
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• 2009

귀리추출물에 L. delbrueckii subsp. bulgaricus 또는 S. salivarius subsp. thermophilus를 단일균주로 발효한 것에 비하여 L. delbrueckii subsp. bulgaricus와 S. salivarius subsp. thermophilus를 혼합하여 발효하는 경우에는 미생물균수와 산 생성이 증가하였다. pH의 변화에서도 S. salivarius subsp. thermophilus의 경우가 L. delbrueckii subsp. bulgaricus보다 더 낮은 pH를 나타내었으며, L. delbrueckii subsp. bulgaricus와 S. salivarius subsp. thermophilus를 혼합하여 발효하는 경우에는 pH가 더 빠르게 감소하였다. 이러한 결과는 우유를 원료로 한 요구르트의 경우처럼 귀리추출물의 젖산발효에서도 L. delbrueckii subsp. bulgaricus와 S. salivarius subsp. thermophilus의 두 균주 간에 생육촉진 현상이 있음을 의미하는 결과로 해석될 수 있는데 그 정도는 매우 적었다. 본 실험에서 S. salivarius subsp. thermophilus의 미생물균수와 산 생성이 더 증가한 반면 pH는 더 낮은 이유는 L. delbrueckii subsp. bulgaricus에 비하여 귀리추출물에 더 잘 적응하였기 때문이라고 생각된다.