• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.9
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• pp.1211-1218
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• 2007

The aim of this study was to compare the fermentability and characteristics of fermented broths for white ginseng, red ginseng and extruded white ginseng at $110^{\circ}C$ (A), $120^{\circ}C$ (B) and $130^{\circ}C$ (C). The scanning electron microphotograph of B and C was uniform aircell distribution, but A had increased pore size and exploded some aircell's wall. Saccharification rate constant of C was the highest (10.123 $mg/mL·hr^{1/2}$). Fermentation temperature was $27^{\circ}C$ for 30 days and the cultivation was fixed with Saccharomyces cerevisiae, Aspergillus usamii, and Rhizopus japonicus. The pH of red ginseng fermented broth was 3.79, which was the highest among the fermented samples. The fermented broth of B had the highest acidity (4.46%). The fermented broth of A had the highest reducing sugar content in ginseng suspensions (32.36 mg/mL). In ginseng fermented broths, reducing sugar content was decreased rapidly during the initial 5 days and alcohol content was increased during the initial 5 days. On the fifth day, the fermented broth of C showed the highest alcohol content (5.20%).

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1979.10a
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• pp.248.2-248
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• 1979

식초산 발효 실험을 통하여 다음과 같은 결과를 얻었다. 1. 자연에서 초산균 52균주를 분리하고 그중 식초산 농도 5.5% 이상되는 초산균 CAU-4, CAU-15, CAU-17, CAU-46, 4균주를 선별하였다. 2. 정치배양과 진탕배양을 실시한 결과 산생성랑은 진탕배양에서 월등한 효과를 보였다. 3. 유기태 질소원의 첨가시 peptone을 0.4%까지 증가를 보였고, yeast extract는 0.1~0.2%가 최적량이고 그 이상은 산량이 감소되었다. 4. $NH_4NO_3의$ 자화성을 조사한 결과 CAU-17만이 자화하지 못하였고, 무기태 질소원으로서는 $(NH_2)_2CO가$ 가장 좋았다. 5. 무기염류는 $KH/_2PO_4,$ $MgSO_4.7H_2$ O 0~0.1% 첨가하여 약간의 효과를 보았다. 6. Glucose의 첨가량별 산량의 증가는 0.25% 첨가시 0% 첨가시 보다 증가를 보인 반면 1% 첨가시는 오히려 감소하였다. 7. 초발 alcohol농도가 낮을수록 유도기와 대수기가 단축되며 10%이상에서는 4균주 모두 산을 생성하지 못하였다. 8. 초발산도가 높을 경우 유도기가 길어지고 산생성량이 줄어 들었다. 9. 초산균의 배양온도는 $30^{\circ}C,$ $35^{\circ}C에서$ 산생성 속도가 가장 빨랐다. 10. 발효시 산생성량에 따른 세균수의 증가는 접종후 2~3일 사이에 가장 많았다. 11. 초산의 증가와 더불어 균체량은 증가하였고 pH는 약간색 감소하나 PH는 2.5이하로는 내려가지 않았다. 12. alcohol 잔량은 발효 개시 후 5 ~6일의 정지기에 가장 낮았다.

• Journal of Life Science
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• v.14 no.1
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• pp.167-173
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• 2004

The optimal conditions for the continuous production of $\gamma$-aminobutyric acid by immobilization of Lactobacillus brevis BH-21 using column type reactor were investigated. The optimal conditions of operation were 2.2 mm diameter bead of 3.0% sodium alginate at 10 mL/h of substrate feeding rate. Continuous production by immobililzed cells showed the highest productivity with replacement of fresh medium in every 48h for fourth fermentatoin cycle following the rendition of $\gamma$-aminobutyric acid productivity. A productivity of $\gamma$-aminobutyric acid could be obtained for 25 days by continuous column type reactor under optimal conditions.

• Microbiology and Biotechnology Letters
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• v.19 no.5
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• pp.487-490
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• 1991

In this study continuous alcohol fermentation of molasses by the recirculation system has investigated. After cultivation of yeast cells in the YPD medium with increasing the medium concentration from 10 to 183.5 g/l stepwisely, the fermentation medium was replaced by molasses. The maximum cell mass was 25 g/l, and the mean cell mass during the operation was 23.5g/1, which was 3.4 times higher compared with a conventional batch system. The optimum fermentation conditions with feeding molasses of 180 g/l were obtained when the fermentation was carried out at 500 rpm and at the dilution rate of 0.037 $h^{-1}$. Under these conditions we could safely operate the fermentor for 645 h without any trouble. The maximum alcohol productivity was 4.9 g$l\cdot h$ with an alcohol concentration of 53.9 g/l at the dilution rate of 0.091$h^{-1}$.

• The Korean Journal of Mycology
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• v.32 no.2
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• pp.105-111
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• 2004

The changes of microflora and chemical characteristics during fermentation process of cotton waste for oyster mushroom cultivation were investigated with 5 l bench-scale reactors placed in an incubator at different temperatures ($40,\;50\;and\;60^{\circ}C$). Cotton waste was wetted to 70% moisture, and air flow rates to the substrate were 50, 100 and 300 cc/min. In processing of composting, the mesophilic bacterial population decreased sharply but thermophilic bacterial population increased. In case of fungi, both mesophilic and thermophilic population decreased. The daily $CO_2$ evolution showed little difference in all treatments, while $NH_3$ dropped sharply after 3 days. The desirable composting temperature and air flow based on the mycelial growth of oyster mushroom were $50^{\circ}C$ and 100 cc/min, respectively.

• Food Science and Preservation
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• v.8 no.3
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• pp.320-325
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• 2001

In fermentation characteristics, R2 was suitable for fast start and fermentation, while UCD530 was tool suitable far complete fermentation at 25$^{\circ}C$. T73 and AC- strains produced much more total acid compared to other strains and it was concerned with producing large amount of succinic acid and acetic acid. OC-2, UCD530, Beaujolais, and BC strains revealed low fermentation efficiency (below 62.0%), but EC1118, RC212, T73 and BM45 strains showed opposit result (above 70.0%). D254 and Wadenswil 27 seemed to have excellent cohesive ability because these two yeast strains made somewhat hard precipitation at the bottom after complete fermentation. T73 and CEG gave higher amounts of acetic acid (above 630 mg/L), while UCD530, W-3 and Beaujolais recorded low concentration (below 200 mg/L). In sulfur dioxide tolerance, preferable culturing temperature and times were 25$^{\circ}C$ and 72 hr respectively. The strains R2, BM45 and L2056 revealed high sulfur dioxide tolerance (above 30mg/L), white 71B, Wadenswil 27 and Beaujolais showed the opposite result (below 5mg/L)

• Korean Journal of Food Science and Technology
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• v.32 no.1
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• pp.187-191
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• 2000

This study was performed to examine the effects of salt addition level on the changes in physicochemical properties of the salted and fermented shrimp during fermentation. Amino nitrogen content increased with the fermentation time, and was higher at low salt addition level. Volatile basic nitrogen content in the fermented shrimp with 3 and 8% salt increased rapidly at initial fermentation period, but decreased at 6 week fermentation and remained constant afterward, while that with 18 and 30% salt maintained its initial level through 22 week fermentation. Thiobarbituric acid(TBA) value decreased rapidly in the early stage of the fermentation, but slightly increased after 4-6 week fermentation. The TBA value was higher at lower salt level after 6 week fermentation. Peroxide value of the fermented shrimp with salt content higher than 8% increased rapidly at 2-4 week fermentation and decreased sharply at 6 week, while that with 3% salt showed the maximum value at 10 week fermentation.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1978.10a
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• pp.206.1-206
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• 1978

발효공업에 있어서 오염에 영향을 주는 미생물의 열살균 속도를 $120~130^{\circ}C$ 범위에서 조사하였다. 살균속도에 대한 온도의 영향은 Arrhenius식으로 다음과 같이 표시되었다. K=3.47$\times$$10^{28}$ EXP(-52.3 Kcal/RT)원형 반응기의 비이상혼합효과를 보기 위하여 난류영역에서 methylene blue 용액을 사용하여 계단압력을 주어 그 과도응답을 측정한 결과 체류시간 분포는 dispersion 모형에 잘 부합되었고 peclet number 100 을 얻었다. 당밀을 열분해시키면 hydroxymethl furfural이 생성되는 것을 확인하였고 온도와 pH에 따라 검토한 결과 고온의 산성용액에서 반응은 촉진되었다.

• Korean Journal of Food Science and Technology
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• v.38 no.6
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• pp.785-792
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• 2006

The characteristics of alcohol fermentation using sweet persimmon juice were studied in static fermentation in an effort to develop new types of functional wine. The yeast strain Saccharomyces cerevisiae KCCM 12650 was selected for use in the fermentation of sweet persimmon juice. Attempts were made to modify the sweet persimmon juice in order to find suitable conditions for alcohol fermentation. The modified sweet persimmon juice (pH 4.0) that was most suitable for alcohol fermentation contained $24^{\circ}Brix$ of sugar supplemented with sucrose as a carbon source and 0.5 g/L of $(NH_4)_2HPO_4$ as a nitrogen source. After 5 days of fermentation at $25^{\circ}C$, 12.8% of alcohol was produced from the modified juice and its pH was slightly decreased to 3.9. Browning of the wine was observed during storage due to the oxidation of phenolic compounds. The initial browning of 0.08% at $OD_{420}$ after fermentation increased to 0.40 during storage for 11 weeks at room temperature. The addition of $K_2S_2O_5$ was effective in delaying the browning of the wine. The browning of the wine decreased to 0.25 at $OD_{420}$ with the addition of 200 mg/L of $K_2S_2O_5$. The wine produced in this study contained some organic acids such as malic acid (6.82% g/L) and succinic acid (1.40 g/L), some minerals such as $K^+$ (947.8 mg/L) and $Mg^{2+}$ (36.4 mg/L), as well as soluble phenolics (779 mg/L of gallic acid equivalent). Schisandra fruit was added to the sweet persimmon juice during alcohol fermentation in order to improve the sour taste and flavor. The best sensory quality (taste, flavor, and color) was obtained by adding 0.5% schisandra fruit.

• Korean Journal of Food Science and Technology
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• v.36 no.4
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• pp.609-615
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• 2004

Old rice showed higher initial pasting and peak viscosity temperatures than new rice. Reducing sugar contents of rice harvested in 1998 were lowest 24hr after digestion with saccharification enzyme, but similar after 36hr, among rice samples tested. Fermentation characteristics and preference of Takju made by fermenting raw rice harvested from 1998 to 2001 far 7 days were investigated. Alcohol contents during Takju brewing rapidly increased for 5 days to 17.3-18.1%, and were 17.5-18.2% on day 7, with those of Takju brewed with rice harvested in 1998 being highest in both cases. Sensory evaluation results showed Takju fermented with rice harvested in 2000 had highest sweetness, preference, and sourness, and that fermented with rice harvested in 1999 had highest sourness, but no voluntariness was shown between each other (meaning not clear). Moisture contents and gelatinization characteristics of old and new rice were slightly different, although factors adversely affecting Takju such as flavor of old rice did not appear in sensory evaluation probably because old rice was stored in rice bran farm for long times and used after milling. Results reveal surplus old rice could be utilized for Takju brewing.