• Journal of Life Science
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• v.19 no.11
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• pp.1538-1546
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• 2009

This study was conducted to estimate the in vitro fermentation characteristics and in situ degradabilities of total mixed rations fermented by the synbiotic co-cultures composed of various anaerobic microorganisms in the rumen of cow. Seventy two TMR bags (4 treatments $\times$ 6 fermentation days $\times$ 3 replications) were manufactured for in vitro and in situ experiments. The experiment was composed of four treatments including the control, the mould and bacteria synbiotics (T1), the mould and yeast synbiotics (T2) and the bacteria and yeast synbiotics (T3). Each treatment had six fermentation days (1, 3, 5, 7, 14, 21 day) with three replications. Two rumen cannulated Holstein cows (550 ㎏ of mean body wt) were used for in situ trial, and a total of 96 nylon bags were retrieved from the rumen according to eight fermentation times (1, 3, 6, 9, 18, 24, 48 and 72 hr). The mean fermentation temperatures of TMRs by supplementation of anaerobic micoorganism co-cultures ranged from $22.97^{\circ}C$ to $26.07^{\circ}C$, and tended to increase steadily during the entire period. pH values of the F-TMRs ranged from 4.39 to 4.98 and tended to decrease with the extension of the fermentation period, and decreased by supplementation of synbiotics (p<0.05). The ammonia concentrations of F-TMRs were not affected by addition of synbiotic co-cultures during the early fermentation period (within 7 days), but was lowest (p<0.05) in T3 during the late fermentation periods (after 14 days). Lactic acid concentration of F-TMR was lowest in T3 at 1 day of fermentation, but was not different from treatments in the other fermentation days. Microbial growth rates of F-TMR reached a peak at 7 days of fermentation, and afterward tended to decrease. In in situ experiment, the DM disappearance rates were higher in T1 than the control during early fermentation times (within 3 hours), but was vice versa at 48 hours of fermentation (p<0.05). There was no significant difference in effective DM degradability among treatments. NDF and ADF disappearance rates in situ were similar to those of DM. From the above results, the supplementation of synbiotics, particularly the mould and bacteria synbiotics, resulted in improving the pH and concentration of lactic acid of F-TMR as parameters of fermentation compare to the control, and also had higher in situ disappearance rates of DM, NDF and ADF than the control at early fermentation time. However, effective DM degradability was not affected by supplementation of synbiotics.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.2
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• pp.257-262
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• 2011

The objective of this study was to investigate the changes in the microbial properties of taurine supplemented Kimchi during fermentation at $6^{\circ}C$ for 46 days. Chinese cabbage was brined in 10% salt solution for the control Kimchi and in 10% salt solution containing 1, 2 or 4% taurine (w/w, based on cabbage) for taurine supplemented Kimchi (Taurine I, II, and III groups, respectively). The pH values of all the groups dramatically decreased after 1-day of fermentation. Total numbers of viable cells were highest at 5-days of fermentation for the control, at 9-days of fermentation for Taurine I, and at 23-days of fermentation for Taurine II and III. The highest numbers of lactic acid bacteria were found at 9-days of fermentation for the control and Taurine I, and at 18-days of fermentation for Taurine II, and at 13-days of fermentation for Taurine III. The fermentation periods required to reach the highest numbers of Leuconostoc bacteria for Taurine I, II and III were longer than that for the control, suggesting that taurine might inhibit the growth of Leuconostoc bacteria during Kimchi fermentation. Based on the results obtained from the present study, it is concluded that adding taurine to the production of Kimchi could delay the ripening period of Kimchi.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.8
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• pp.1226-1231
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• 2005

In order to improve qualities of traditional kochujang, pear juice was added to kochujang, and the physicoche-mical and microbial characteristics of pear-added kochujang were investigated for 2 months of fermentation at 30$^{\circ}C$. Moisture contents of pear-added kochujangs increased except of 9$\%$ pear-added kochujang and crude protein contents of them decreased as the fermentation proceeded. Total sugar contents of pear-added kochujangs did not change during the fermentation period, and reducing sugar contents of them increased remarkably from early stage of fermentation. The pH of pear-added kochujangs decreased and titratable acidity of them increased during fermentation. Amino-nitrogen contents of pear-added kochujangs increased remarkable after 45 days of fermentation. Viable cells counts of yeasts in pear-added kochujangs increased to 2.2$\∼$2.9$\times$$10^{3}$CFU/g, and bacterial cell counts were in relatively constant range of 2.1$\∼$2.9$\times$$10^{7}$CFU/g at the late stage of fermentation. Color of pear-added kochujangs had no difference and 'a' value decreased slightly during fermentation. The result of sensory evaluation showed that 6$\%$ pear added kochujang were more acceptable than others.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.6
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• pp.1034-1042
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• 2004

This study was carried out to investigate preparation of reconstructed red peppers, effects of pungency and redness of red peppers on the Kimchi quality using central composite design and response surfaces methodology. Capsaicinoids and ASTA (American Spice Trading Association) value put in X$_1$, X$_2$ of independent variable. The result of response surface regression analysis of reconstructed red peppers, correlation coefficient ($R^2$) of overall pungency intensity, persistence and degree of redness was 0.935, 0.935 and 0.821, respectively. After it was made Kimchi samples with reconstructed red peppers, it was examined pH, titratable acidity and lactic acid bacteria of its during fermentation. In the initial fermentation period of Kimchi, it showed pH of 5.46∼5.78, titratable acidity of 0.27∼0.31%, salt content of 2.26∼2.48% and lactic acid bacteria of 4.05${\times}$10$^{5}$ ∼6.23${\times}$10$^{5}$ , respectively. And it showed traditional fermentation pattern in the pH, titratable acidity and microbes of the middle (appropriate fermentation) and last (excessive) fermentation period. While capsaicinoids content in the Kimchi decreased a little according to extend fermentation period, ASTA value showed low correlation reconstructed red pepper and fermentation period. Also, it was analyzed correlation coefficient ($R^2$) of independent variables (capsaicinoids, X$_1$; ASTA value, X$_2$) between sensory attribute in the Kimchi during fermentation. The result of regression analysis, $R^2$ in the overall pungency intensity, persistence and degree of redness showed 0.515, 0.675, 0.784, respectively.

• KSBB Journal
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• v.13 no.3
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• pp.325-330
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• 1998

The methylotrophic yeast, Pichia pastoris, is known to be a potential host to offer many advantages for production of recombinant proteins. Fermentation parameters were optimized to enhance the heterologous ${\beta}$-galactosidase productivity with P. pastoris. Optimum concentration of methanol, used as inducer, was observed to be 8 g/L and the extent of repression of AOX1 promoter by glycerol was lower than by glucose. The degradation of the gene product ${\beta}$-galactosidase by protease was inhibited as the pH increased from 5 to 8 and the yeast extract(1%) as nitrogen source increased expression level 4 times higher compared to yeast nitrogen base(1%) as nitrogen source increased expression level 4 times higher compared to yeast nitrogen base(1%). Induction method, in which methanol is just added to fermentation medium without centrifugation, was found to be as much effective as the one with centrifugation.

• The Korean Journal of Food And Nutrition
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• v.1 no.2
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• pp.95-101
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• 1988

In order to produce lactic acid and calcium lactate very useful for foods and medical supplies, lactic acid fermentation was studied by Lactobacillus sporogenes, a spore forming lactic acid bacterium. When this bacterium was cultured aerobically in the spore forming medium, the spore forming rate was 96.0% as total cell number 20$\times$108/ml, spore number 19.2$\times$108/ml. One minute agitating every 1 hour in the flask culture, or agitation of 100rpm in the fermenter was most efficient to continue to ferment at 45$^{\circ}C$ for 4days in the fermentation medium containing 10% glucose as carbohydrate and CaCO3 as a neutralizing agent. This homofermentative lactic acid bacterium showed fermentation yield of 99.3% and more than 98.2% of the yield was L(+)-lactic acid.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.1
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• pp.102-106
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• 2005

This study was carried out to find the attributes for liquid-type yogurt with Lactobacillus casei 911LC during 72 h fermentation at $37^{\circ}C$. The pH decreased up to 32 h and plauteaued thereafter, and the titratable acidity increased up to 40 h. The growth of lactic acid bacteria sharply increased with $3.5{\times}10^7$ cfu/ml up to 40 h of fermentation and slowly decreased thereafter. The free amino acids produced during fermentation reached the maximum value at 44 h and gradually decreased thereafter. Bitterness sensory scores were the highest at 44 h of fermentation. In the result of electrophoresis, the band mostly disappeared at 72 h fermentation. The present data showed that the range of optimum fermentation time for liquid-type yogurt using Lactobacillus casei 911LC was from 40 to 44 h.

• KSBB Journal
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• v.10 no.3
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• pp.231-236
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• 1995

For continuous ethanol production In an immobilized cell reactor consisting of Saccharomyces sake, feedings of one tenth to three tenths times diluted fermentation media were effective for maintaining the high ethanol productivity and physical stability of immobilized beads. In case two tenths times dilltued one of the fermentation medium supplemented with egg albumin hydrolysate(0.5%) and phosphatidylcholine(0.5%) was fed, a maximum ethanol productivity of $69 g/\ell$-hr was attained at a dilution rate of$1.1lhr^{-1}$, and it was 50% higher than that of the two tenths times diluted one of the fermentation medium without any supplement, $46 g/\ell$-hr.

• Korean Chemical Engineering Research
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• v.50 no.5
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• pp.879-884
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• 2012

In this present study, Aspergillus niger NRRL 567 was cultivated on an inert support material and the effects of various fermentation parameters including temperature, nutrient solution pH, inoculation level, and moisture content were observed and optimized by one-factor-at-a-time (OFAT) and response surface methodology (RSM), sequentially. It was found that the incubation temperature of $30^{\circ}C$ with 75% moisture content, nutrient solution pH of 7.1 and inoculation level of $4.0{\times}10^6$ spores/ml were the most favorable. Again, fermentation parameters were optimized using RSM. The determined optimum condition is $26.5^{\circ}C$, pH 9.9, 75.1%, and $6.0{\times}10^6$ spores/ml. Under this optimized condition, A. niger NRRL 567 produced 118.8 g citric acid/kg dry peat moss at 72 hr. Maximum citric acid production of optimized condition by RSM represented a 1.6-fold increase compared to that obtained from control experiment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.5
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• pp.800-806
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• 1997

Effect of temperature on Kakdugi during fermentation was investigated by measuring sensory, physicochemical and microbiological, properties up to 57 days. The diced(2.5$\times$2.5$\times$2.5cm) Chinese radishes(Ra-phanus sativus L.) with other ingredients were fermented under the different temperatures. Kakdugi were stored at 4$^{\circ}C$ after keeping at 2$0^{\circ}C$ for 12 hours(treatment E) from initial fermentation to the end at each temperature on preparation. The pH was decreased to the range of 4.14~4.29 in the initial of pH 5.8, and total acidity was increased 2~4 times more than that of in the initial period (0.24%). And the changes of treatment A, B, and C were nearly constant up to 57 days in the range of 0.80~0.88% (pH 4.1). The changes of vitamin C showed sigmoidal curve, increasing significantly in the palatable period after decreasing gradually in the initial period. The content of vitamin C in treatment E was rapidly decreased, but that of treatment C was kept high content up to 57days. the number of lactic acid bacteria was remarkably increased in palatable period and was gradually decreased thereafter. The scores of aroma, taste, overall acceptability in sensory evaluation during the fermentation was high in order of treatment E, C, D, B and A. The scores of sensory evaluation treatment D and E during fermentation was rapidly decreased, however, treatment A, B and C were maintained. Changes of lactic acid bacteria, and sensory properties, among treatment A, B and C which kept a good quality up to 57 days, had high scores of sensory evaluation, abundant vitamin C in the palatable period. The result showed that Kakdugi fermented at 4$^{\circ}C$ after keeping at 2$0^{\circ}C$ for 36 hours had better taste and quality than those of other treatments.