• 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.

• Food Science and Preservation
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• v.7 no.2
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• pp.228-232
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• 2000

To utilize abundant potatoes effectively, it was studied on alcohol fermentation strains which were isolated and identified. Fifteen yeast strains with high alcohol fermentation ability were isolated from rotted potatoes. Among them, two isolated strains, 5-3A and 10-4B showing the highest alcohol fermentation ability were identified as Zygosaccharomyces fermentati based on the morphological and physiological characteristics. Their optimum conditions for the alcohol fermentation in 25% glucose were pH 3.0, 30$^{\circ}C$ and 150 rpm of shaking speed, respectively.

• The Korean Journal of Food And Nutrition
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• v.26 no.3
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• pp.358-365
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• 2013

The study was conducted to investigate the condition for mixed fermentation of Rhodilola sachalinensis with red ginseng using Lactobacillus acidophillus 128 and the changes of physicochemical properties and antioxidant activities before and after the lactic acid fermentation was examined. In the single fermentation of Rhodiola sachalinensis extract, the pH and titratable acidity rarely changed, and the number of lactic acid bacteria decreased greatly. On the other hand, in the lactic acid fermentation of Rhodiola sachalinensis-red ginseng mixed extract of 50% red ginseng content, the pH decreased, whereas the titratable acidity and the number of lactic acid bacteria increased. The solid content of optimal mixed extract for lactic acid fermentation was 0.5%. Sugar content decreased during fermentation, but total phenolic compounds tended to increase during fermentation. The salidroside and p-tyrosol content of the initial Rhodiola sachalinensis-red ginseng mixed extract was 419.5 mg% and 60.1 mg%, respectively; after fermentation, the salidroside content after lactic acid fermentation decreased greatly to 81.8 mg%, and the amount of p-tyrosol increased greatly to 324.9 mg%. The DPPH scavenging activity of Rhodiola sachalinensis-red ginseng mixed fermentate was 78.1% at 0.1% concentration, showing a tendency to increase as compared to 50.3% of Rhodiola sachalinensis-red ginseng mixed extract before the fermentation (p<0.05); it was a higher antioxidant activity as compared to the single fermentation of Rhodiola sachalinensis or red ginseng.

• Food Science and Biotechnology
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• v.16 no.5
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• pp.812-816
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• 2007

To overcome the problem of ginseng's earthy smell in the manufacture of ginseng wine, we used dried ginseng powder that was extrusion-cooked at $125-168^{\circ}C$ in the wine making process. By using a ginseng powder that was extrusion-cooked at higher temperatures, fermentation by Maillard reaction products (MRPs) was delayed, and the acidic pH that results from extrusion cooking was improved. At $15^{\circ}C$ with glucose instead of sucrose, an addition of 0.5%(w/v) diammonium phosphate (DAP) to the $125^{\circ}C$ extrusion-cooked ginseng powder reduced the primary fermentation time to 11 days versus 33 days without DAP. In the absence of DAP, by increasing the fermentation temperature from 15 to $30^{\circ}C$, increasing the starter yeast inoculate from 0.02 to 1 %, and by increasing the amount of ginseng extrudate from 1 to 2%, fermentation time was effectively reduced more than 10-fold. The results of this study may provide information for the alcohol fermentation of materials containing MRPs as well as for poor nitrogen sources.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2001.05b
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• pp.121-125
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• 2001

For the probiotic feed production, aerobic liquid fermentation of pulverized food wastes was attempted with a yeast Kluyveromyces marxianus. After grinding finely, optimal fermentation conditions of the substrate was investigated by shaking culture. The most active growth of the yeast was shown at solid content of 10%. The proper addition of urea(0.5g/l), o-phosphate(0.4g/l), molasses(4g/l), and yeast extract (1g/1) increased cell growth rate and viable cell count. For optimizing, the nutrients were all added to substrate and fermentation was carried in 2 litre jar fermenter. For the stimulation of hydrolyzing enzyme excretion, mixed culture with Aspersillus oryzae was also conducted. In 12 hours of fermentation, viable cell count of the yeast Kluyveromyces marxianus amounted to the number of 1.4 $\times$10$^{10}$ /1 in the culture medium.

• 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.

• Proceedings of the Korean Society of Community Living Science Conference
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• 2011.10a
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• pp.114-115
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• 2011

• Korean Journal of Agricultural Science
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• v.46 no.1
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• pp.173-182
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• 2019

To produce a high-quality Kimchi product, molten salt was used for the Kimchi. Changes in the physiochemical properties and functional compounds were analyzed during fermentation. The salinity of bay salt Kimchi was higher than that of the molten salt Kimchi. The fermentation speed of the lactic acid bacteria in the molten salt Kimchi was significantly faster. To evaluate the effects of the salts on the changes in the functional compounds during fermentation, the antioxidant activity, total phenolic compounds (TPC), flavonols, phenolic acids, and glucosinolates in Chinese cabbage were analyzed. In the first 9 days, antioxidants were decreased during this fermentation period and then, increased after that. TPC was slightly increased for all the conditions after 40 days fermentation. Kaempferol was a major flavonol but had a relatively larger decrease in the molten salt Kimchi than in the bay salt samples. Phenolic acid did not show any significant difference among the samples. The glucosinolate contents were significantly decreased in all the conditions of Kimchi during the fermentation period. Consequently, the molten salt greatly affected the fermentation speed of Kimchi and the total characteristics of the Kimchi lactic acid bacteria. Although the functional compounds of Chinese cabbage were decreased during the fermentation of Kimchi, this decrease did not profoundly deteriorate the food quality. Therefore, high-quality Kimchi with enhanced bioactivity will be available if appropriate Chinese cabbages that have enhanced functional compounds are used.

• Food Science of Animal Resources
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• v.25 no.2
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• pp.226-231
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• 2005

This study was carried out to find the physico-chemical attributes of yogurt base with Lactobacillus case; 00692 during 72 hr fermentation at $37^{\circ}C$. The pH decreased up to 44 hr and plateaued thereafter, and the titratable acidity increased up to 40 hr. The number of lactic acid bacteria sharply increased with $1.0\times10^7cfu/mL$ up to 48 hr of fermentation and slowly increased thereafter. The free amino acids produced during the fermentation reached the maximum value at 40 hr and gradually decreased thereafter. In the result of electrophoresis, the band was the thickest at 44 hr and mostly disappeared at 72 hr fermentation. The present data showed that the range of optimum fermentation time for yogurt base using Lactobacillus casei 00692 was from 40 to 44 hr.

• Journal of Environmental Science International
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• v.15 no.10
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• pp.975-982
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• 2006

This study has been conducted to optimum operating conditions for effective acid fermentation according to OLR(organic loading rate) in the mesophilic and thermophilic acid fermentation process. The results are summarized as follows. In order to obtain reasonable acid fermentation efficiency in performing acid fermentation of food wastes in thermophilic condition, organic loading rate was required below 20 gVS/L.d. As $SCOD_{Cr}/TKN,\;SCOD_{Cr}/T-P$ of thermophilic acid fermented food wastes In organic loading rate 20 gVS/L.d were 18.9, 73.4 respectively, it was possible to utilize as external carbon source for denitrification in sewage treatment plant after solid-liquid separation as well as co-digestion of fermented food wastes and sewage sludge.