• Microbiology and Biotechnology Letters
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• v.22 no.6
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• pp.659-664
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• 1994

In order to predict gas hold-up and oxygen transfer rate during sisomicin fermentation employing air lift fermentor, simulated media similar to fermentation broths in rheological proper- ties were prepared and used. Rheological properties of fermentation broths from 40 hours and 60 hours of cultivation were analyzed by applying to Power's Law equation. Regardless of addition and no addition of MgSO$_{4}$, the tendencies, that n value was decreased and K value was increased as aeration rate was increased, were shown. Simulated media of twelve different fermentation broths were formulated in a range of 0.7 to 2.1% CMC, and the values of gas hold-up and k$_{L}$a depending on superficial air velocity were measured using these simulated media. And the relation- ships, $\varepsilon$=$\alpha$U$_{Gr}$$\beta$, K$_{L}$a=$\gamma$U$_{Gr}$$\delta$ were obtained, and these equations are thought to be used to predict the values of gas hold-up and k$_{L}$a during fermentation.

• Korean Journal of Food Science and Technology
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• v.42 no.1
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• pp.82-89
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• 2010

To obtain functional materials from a submerged culture of Hericium erinaceum, a suitable basal medium for flask culture was screened and the optimal culture conditions in a jar fermenter were investigated with the addition of ginseng extracts (GE) to the basal liquid medium. Of all tested basal liquid media, the mushroom complete medium (MCM) supplemented with 0.5% of GE produced the highest mycelial dry weight (MDW) of 5.91 g/L in the flask, which reached a plateau at $25^{\circ}C$, pH 5.5 after 10 days. The submerged culture conditions for the mass production of mycelia in a 50 L jar fermenter were also optimal at $25^{\circ}C$, pH 5.5, 120 rpm agitation speed and 0.4 vvm aeration rate. Under these conditions, the maximum MDW was produced, which reached a value of 4.28 g/L within 5 days. When we investigated the effects of the amount of GE in the MCM on the production of MDW in the jar fermenter, the addition of 5% GE (HE-GE-5) under the optimal culture conditions produced the maximum MDW (4.93 g/L). In addition, the crude polysaccharide of HE-GE-5 contained mainly neutral sugars (63.2%) with considerable amounts of uronic acid (19.3%) and a small amount of proteins (8.8%) and it had potent immunostimulation properties.

• Food Science and Preservation
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• v.13 no.3
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• pp.329-336
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• 2006

The characteristics of mash qualities of takju prepared by addition of chestnut peel powder(5%, 10%, 20% and 30% per steamed rice) were investigated during fermentation. That is, in all fermentation periods, changes of pit total acid, organic acids, solids, amino nitrogen, total sugar and reducing sugar, microorganisms, alcohol and color were determined and analyzed. There was significant differences in characteristics of mash qualities by addition of chestnut peel powder. In general, contents of total acid, organic acids, amino nitrogen, total sugar, reducing sugar and ethanol of takju added with chestnut peel powder were lower than those of steamed rice only, whereas solid contents was higher. But ethanol content of takju added with 5% of chestnut peel powder after 8 days of fermentation was 9.6% which was similar to that of takju prepared by addition of steamed lice only. Also, microbial populations such as total viable cells, yeast and lactic acid bacteria of the treatments were increased to about $10^8CFU/mL$ after 2 days of fermentation and then decreased gradually. In the beginning stage of fermentation color differences value of the treatments were $1.99{\sim}10.27$, and the differentials reduced gradually during fermentation.

• Microbiology and Biotechnology Letters
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• v.26 no.6
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• pp.529-536
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• 1998

In a 20 L fermentor experiments the level of dissolved oxygen (D.O.) strongly affected growth and PHBV production of Azotobacter vinelandii UWD. A higher D.O. (5%) increased specific cell growth rate two folds but PHBV production was 17 folds higher (62.3 wt%) at a lower D.O.(1%) level. D.O. level was not a good criterion to evaluate the effect of aeration on fermentation characteristics of A. vinelandii UWD. This strain maintained an equal D.O. (5%) by decreasing its oxygen consumption rate when oxygen transfer rate (OTR) was decreased by changing agitation speed at a fixed aeration rate. OTR rather than D.O. was a criterion to explain the effect of aeration on the cell growth and PHBV production. At 5% D.O. with a lower 0TR cell growth rate decreased but PHBV production (57.3 wt%) approached to that (62.3 wt%) of the lower (1%) D.O.

• Journal of Animal Environmental Science
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• v.15 no.3
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• pp.271-280
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• 2009

The best way to treat livestock manure is to recycle as much as possible. The composting of livestock manure is a safe and economical treatment process. This study was carried out to investigate decomposition effect of pig manure by adding fermented compost. The fermented compost was added in pig manure mixed with sawdust as an inoculator, and the mixture was fed to composting reactor. Supplemental levels of fermented compost on the pig manure mixed with sawdust were regulated at 5, 10, 15 and 20% (V/V) respectively. The results were as follows ; 1. In all cases, PH range was between 7.6~9.05 during composting period. 2. The highest temperature and the long duration of thermophilic stage were observed in control treatment. 3. The number of microorganism reached at maximum on day 4, which recorded the highest temperature 4. Compost pile mixed with 10% of inoculator (fermented compost) showed the highest C/N ratio reduction.

• Korean Journal of Food Science and Technology
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• v.21 no.6
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• pp.845-850
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• 1989

Effect of high temperature soaking in salt solution and short time microwave heat treatment on quality of Korean pickled cucumbers during fermentation was investigated. The Korean pickled cucumbers were fermented at $25^{\circ}C$ for 10 days in 10% salt solution. The physicochemical properties measured were pH, the total acidity, hardness and the sensory properties of odor, taste and texture were also evaluated. The result showed that the effect of soaking cucumber in $80-90^{\circ}C$ hot salt solution significantly reduced the fermentation rate and softening rate of texture while a rather rapid fermentation was found for those soaked in $60-70^{\circ}C$. The effect of microwave treatment inhenced fermentation a little for short treatment but it was significantly reduced softening rate of texture by 3 minutes heating. The sensory evaluation of Korean pickled cucumber was found that heat treatments with hot solution and microwave heating had a possitive effect for reduction of softening of cucumber tissue, however odor and taste were not significantly affected.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.6
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• pp.840-846
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• 2015

We investigated blueberry wine made using traditional yeast (Saccharomyces cerevisiae M-5) and Saccharomyces cerevisiae Fermivin which is widely used in wine manufacturing, and measured its fermentative characteristics and antioxidant activity. S. cerevisiae M-5 is a traditional yeast isolated from domestically grown Black raspberry (Rubus occidentalis). Both S. cerevisiae M-5 and Fermivin were inoculated into blueberry juice (BBJ) up to $1{\times}10^9CFU/kg$, followed by incubation at $25^{\circ}C$ for 39 days. Final fermentation products of blueberry fermented with S. cerevisiae M-5 (BBM) presented 13.10% alcohol, $8.42^{\circ}Bx$ of sugar, and 1.183% acidity, and final fermentation products of blueberry fermented with Fermivin (BBF) presented 14.20% alcohol, $8.2^{\circ}Bx$ of sugar, and 1.153% acidity. The contents of total polyphenol and flavonoid compounds of BBM were higher than those of BBF and BBJ. DPPH and ABTS radical scavenging activities and reducing power of BBM were higher than those of BBF. The sensory evaluation revealed that BBM showed excellent flavor, taste, and overall acceptability compared with BBF. Based on these results, the possibility of industrial utilization of S. cerevisiae M-5 as traditional yeast was confirmed by sensory evaluation and antioxidant activity. Fermentation rate of S. cerevisiae M-5 was similar to Fermivin, which is used in the food industry.

• KSBB Journal
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• v.21 no.5
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• pp.366-370
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• 2006

In this research, analysis of UDP-glucose a precursor of ${\beta}$-1,3-glucan by high performance liquid chromatography(HPLC) was established using a reversed phase system. One of key metabolite UDP-glucose was selected and its concentration changes was measured with the change of fermentation conditions. The effects of fermentation conditions with/without nitrogen source for cell growth on ${\beta}$-1,3-glucan production were dependent on the UDP-glucose concentration. The UDP-glucose was synthesized rapidly during cell exponential growth period and maintained high during ${\beta}$-1,3-glucan production period. The UDP-glucose concentration was higher for ${\beta}$-1.3-glucan production fermentor than that for cell growth fermentor. The ${\beta}$-1,3-glucan production was optimal at pH 5.5 and synthesis of ${\beta}$-1,3-glucan was greatest at pH 5.5.

• Journal of the Korea Organic Resources Recycling Association
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• v.20 no.3
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• pp.83-88
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• 2012

The algal bloom, resulting from eutrophication, has caused serious water quality problems in river and lake. Therefore, it has to be removed by any means including physicochemical or biological treatment for preserving water quality. This study was conducted to investigate the microalgae removal and energy production using combined electro-flotation and anaerobic hydrogen fermentation processes. The result showed that algae removal efficiency based on chlorophyll a removal increased with the current. At a current of 0.6A, the maximum microalgae removal efficiency of 95.9% was achieved. The treatability of anaerobic hydrogen fermentation was investigated to recover energy from microalgae removed by electro-flotation. The ultimate hydrogen yields of algae before and after ultrasonic pretreatment were 17.3 and 61.1 ml $H_2/g$ dcw(dry cell weight), respectively. The ultrasonic pretreatment of algae led to 3.4-fold higher $H_2$ production due to the increase of hydrolysis rate.

• Korean Journal of Food Science and Technology
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• v.46 no.1
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• pp.33-38
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• 2014

In this study, we investigated the effect of the amount of water added prior to fermentation on the quality of bokbunja (Rubus coreanus Miq.) wine produced. Water was added at 0-fold (A), 1-fold (B), 2-fold (C), 3-fold (D), and 4-fold (E) of the fresh bokbunja weight (w/w), prior to fermentation. Although the amount of bokbunja wine obtained after fermentation increased in proportion to the amount of water added prior to fermentation, the total acidity of the bokbunja wine, adjusted for the weight of bokbunja used in the fermentation process, increased. Moreover, the total phenol and flavonoid content (mg) per weight (g) of bokbunja, in (B), (C), (D), and (E) were 2.86-4.42 and 2.58-3.01 times higher, respectively, than those in (A). These data suggest that different types of bokbunja wines can be produced and different contents of total phenol can be obtained by simply changing the amount of water added prior to fermentation.