• The Korean Journal of Food And Nutrition
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• v.26 no.2
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• pp.249-257
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• 2013

This study is being performed to confirm the container effects during the fermentation processes of kimchi. Kimchi fermentation was prepared in the laboratory with four different types of containers; namely, a traditional Onggi vessel (Korean traditional clay pot, TOV), plastic airtight covered Onggi vessel (PAOV), plastic covered vessel (PCV) and plastic airtight covered vessel (PACV). The kimchi fermentation in the different containers was followed by taking samples at 48 hour intervals for 10 days. In all fermentation containers, the pH changes of kimchi were decreased with fermentation days, while salt content was the same for all types of containers. The number of lactic acid bacteria in kimchi were $1.09{\times}10^8$ $CFU/m{\ell}$ at first. But the TOV, PAOV, PCV, and PACV after fermentation for 10 days were $1.42{\times}10^{10}$, $9.13{\times}10^9$, $4.93{\times}10^9$ and $7.46{\times}10^9$ $CFU/m{\ell}$, respectively. The kimchi fermented in the TOV with the most dominant bacterial species were the following 5 strains: Bacillus subtilis, B. licheniformis, B. safensis, Lactobacillus brevis and B. pumilus. The use of different types of containers therefore influenced the number of L. brevis and the four Bacillus species. in kimchi, and may influence the characteristics of the fermented kimchi products. The TOV offered the greatest L. brevis numbers and suggested that it could be the best suited for preparing traditional kimchi fermentation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.4
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• pp.593-598
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• 2011

This research was performed to determine the quality characteristics of steamed bread by the number of times through the fermentation process. The number of fermentations varied from 1 to 5 while the steamed bread was prepared by measuring the duration of fermentation, and samples were analyzed in terms of general ingredients, physical properties, in vitro starch hydrolysis, protein digestibility, and sensory characteristics. Five times of fermentation resulted in significantly higher water content (p<0.01), and single fermentation led to the highest protein content (p<0.01). Protein levels decreased as fermentation was repeated. Single fermentation gave the lowest specific bread volume (p<0.05) and it increased with the number of fermentation times. Physical properties also varied with the number of times of fermentation. With more fermentation, hardness, gumminess, and chewiness decreased (p<0.01), whereas resilience (p<0.01) and cohesiveness (p<0.05) increased. In vitro starch hydrolysis was higher with 5 times of fermentation than with single to 3 times of fermentation (p<0.05). Protein digestibility was also higher with 5 times of fermentation (p<0.05). In sensory evaluations, whiteness scores were higher with 4 to 5 times of fermentation (p<0.01) whereas scores for crumb uniformity were lower with 4 and 5 times of fermentation. Moistness (p<0.01), cohesiveness (p<0.01), and chewiness (p<0.05) showed their highest scores with 4 times of fermentation.

• Food Science and Biotechnology
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• v.18 no.4
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• pp.1035-1037
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• 2009

In this study we analyzed the dynamic changes in microbiota composition during kochujang fermentation at $30^{\circ}C$. During fermentation, the viable cell counts slowly increased and reached $3.2{\times}10^7$ for aerobic bacteria, $8.3{\times}10^3$ for yeast, and $1.4{\times}10^3$ CFU/mL for fungi after 60 days. Bacilli were found to be the most dominant microorganisms throughout the fermentation process. Using the culture dependent method Bacillus subtilis, Bacillus licheniformis, and Bacillus amyloquefaciens were found to be the main species during the early stages of fermentation; however, Bacillus pumilus and Bacillus stearothermophilus became the most dominant species during the late stage of fermentation. In contrast, when the polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) method was used Bacillus ehimensis was found to be the dominant species during the early stage of fermentation and Bacillus megaterium, B. pumilus, B. subtilis, and B. licheniformis were dominant in the ate stages. These results indicate various other Bacillus species rather than just B. subtilis and B. licheniformis might be involved in the fermentation of kochujang.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.6
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• pp.569-573
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• 2009

The biochemical and microbiological changes of the hard clam shikhae were studied during fermentation at $4-18^{\circ}C$ for 45 days. For preparation of the shikhae, the shucked hard clams were blanched into 2% saline solution and were soaked in seasoning solution before mixing with salt, cooked grain and spices. During fermentation, the initial pH steadily decreased from 5.0 to 4.6, but $NH_2-N$ and VBN concentrations increased to 127 mg/100 g and 27.0 mg/100 g, respectively. Alanine, taurine, glutamic acid, and aspartic acid concentrations increased, but arginine concentration decreased by fermentation. The major organic acids of the fermented shikhae were lactic acid, succinic acid and acetic acid. The major free sugar were maltose, glucose and fructose. The concentration of total viable cell ($2.1\times10^5$ CFU/g) and proteolytic bacteria ($1.2\times10^5$ CFU/g) increased to $4.4\times10^8$ CFU/g and $9.8\times10^7$ CFU/g, respectively until day 15 and then slightly decreased. The concentration of yeast ($2.4\times10^3$ CFU/g) increased to $1.6\times10^7$ CFU/g until day 25, but lactic acid bacteria ($5.0\times10^8$ CFU/g) increased to $5.0\times10^8$ CFU/g until day 9. Vibrio species was not detected on the TCBS agar during fermentation.

• Korean Journal of Food Science and Technology
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• v.46 no.2
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• pp.165-172
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• 2014

Mixed fermentation of cow milk was performed by sequential co-cultures with Bacillus subtilis and Lactococcus lactis. After a first fermentation step with B. subtilis for 6 h, the number of viable cells increased to $2.5{\times}10^8$ CFU/mL. The second fermentation step with L. lactis resulted in increased viable cells $1.09{\times}10^{10}$ CFU/mL for 3 days and increased acidity. However, the number of viable B. subtilis cells was decreased greatly to $5{\times}10^1$ CFU/mL following fermentation with L. lactis. Milk proteins were markedly hydrolyzed by the first fermentation after 2 h, and the second fermentation induced curd formation in milk. However, after 4 h, the first fermentation resulted in higher whey separation and 80 mg% tyrosine content. Gamma-aminobutyric acid (GABA) production was dependent upon the degree of protein hydrolysis by first fermentation. Second fermentation resulted in 0.14% GABA. The milk fermented by B. subtilis indicated the rough surface of yogurt depended upon the degree of protein hydrolysis. In conclusion, set-type yogurt was efficiently produced by co-culturing of milk, and fortifying with peptides, GABA, and probiotics.

• Korean Journal of Food Science and Technology
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• v.37 no.1
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• pp.61-66
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• 2005

Korean traditional rice wine Takju and Yakju were manufactured using 2-step-brewing method. To investigate microflora involved in fermentation step, number of microorganisms, pH, titratable acidity, and alcohol contents of Takju and Yakju were measured. In Takju and Yakju, although not significantly, $1.1{\times}10^{8}$ and $2.0{\times}10^{6}\;CFU/mL$ lactic acid bacteria at initial stage of second fermentation decreased to $8.3{\times}10^{6}\;and\;1.0{\times}10^{4}\;CFU/mL$ at the end of second fermentation, respectively. For Takju, micrococci and yeast occupied 80 and 20% at initial stage of second fermentation, whereas bacteria and yeast occupied 35 and 65% at the end of second fermentation, respectively. Yeast occupied 88% throughout the second fermentation of Yakju. The main yeast isolated from both Takju and Yakju was identified as Saccharomyces cerevisiae using API 20C AUX kit. The yeast strain Candida magnoliae was also detected during fermentation of Takju and Yakju.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.12 no.3
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• pp.155-160
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• 1979

Mechanical agitation in fermentation process enhances the fermentation activity of microbes by means of oxygen supply and frequent collision with substrate. However, the fermentation activity of microaerophilic bacteria is inhibited by the excess oxygen resulted from the mechanical agitation. On this account, a a strain of Lactobacillus bulgarius was cultured to know the inhibition effect of the mechanical agitation and determine the optimum conditions for tile process of lactic acid fermentation. The growth rate of L. bulgaricus and the consumption rate of tile substrate revealed an identical pattern in changes. The two rates were constant in the range of the modified Reynolds number of $1\times10^5\;to\;5\times10^5$ while they showed linear increase in the range of the modified Reynolds number of $1\times10^5\;to\;10\times10^5$. Under the conditions of the modified Reynolds number more than $10\times10^5$, the both rates decreased. At the modified Reynolds number of $10\times10^5$, the maximum specific growth rate and the saturation constant of L. bulgaricus were 0.58/hr and 6.74g/l, respectively.

• Microbiology and Biotechnology Letters
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• v.27 no.3
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• pp.230-235
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• 1999

This study was intended to develop a new rice product by the fermentation of saccharified rice solution using Bifidobacterium and to select an appropriate reducing agent to provide the anaerobic condition for the growth of Bifidobacterium during fermentation. The enhancement of the growth of Bifidobacterium in saccharified rice solution was achieved by the treatment of reducing agents such as ascorbic acid and cysteine. The physical and chemical properties of the fermented product were evaluated, and the effect of the reducing agents were compared between ascorbic acid and cysteine. The fermented product with the addition of ascorbic acid shows the lower pH and the higher titratable acidity comparing the product with the addition of cysteine. This indicated that ascorbic acid was more appropriate reducing agent than cysteine for the fermentation of the saccharified rice solution. The number of viable Bifidobacterium in the fermented product with the addition of ascorbic acid(2.2$\times$108~3.4$\times$108CFU/ml) was greater than that with the addition of cysteine (8$\times$107~2.8$\times$108CFU/ml). Ascorbic acid supplement also contributed better sensory properties, such as flavor, taste and overall acceptibility than cysteine supplement did.

• Microbiology and Biotechnology Letters
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• v.26 no.4
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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.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.3
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• pp.389-393
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• 2003

Present study investigate the effect of enzyme supplementation, methods (applied to rumen or enzyme treated diet) compared with no enzyme diet, on rumen fermentation and apparent nutrient digestibility in a $3{\times}3$ Latin square design with three rumen cannulated Korean Native goats. In situ rumen degradation kinetics was studied in three rumen cannulated Holstein steers. Three diets were, no enzyme, 1% enzyme in rumen and 1% enzyme in diet. The enzyme was sprayed onto forage, and the forage: concentrate ratio was 30:70. Degradation kinetics was studied with three enzyme levels (0, 1 and 2%, w/w) and four pre-treatment times (0, 1, 12 and 24 h). Results suggested that enzyme application method did not affect rumen fermentation, ruminal enzyme activity and total tract apparent digestibility. Nutrient degradation rate and effective degradability of DM, NDF and ADF increased with increasing enzyme level and pre-treatment times. Degradation of nutrients was affected by enzymes levels or pre-treatment times. Therefore, it is probable that the improved degradation may be due to the supplemented exogenous hydrolytic enzymes under a certain condition.