• Microbiology and Biotechnology Letters
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• v.20 no.1
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• pp.102-109
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• 1992

The microfloral changes of lactic acid bacteria during Kimchi fermentation at 5, 20 and $30^{\circ}C$ were compared by using various selective media, and the lactic acid bacterial strains were isolated and identified. The patterns of microfloral changes in each lactic acid bacterial group, leuconostoc, lactobacilli, streptococci and pediococci, were similar at different fermentation temperature, and the changes were accelerated by increased temperature. Among them, leuconostoc and lactobacilli showed high population, and at low temperature the number of leuconostoc were higher than at high temperature. Leuconostoc and streptococci were increased in number from the beginning, but they rapidly decreased after the optimum ripening period. Pediococci increased their number after streptococci, but they were rapidly decreased later. Lactobacilli were highly distributed throughout the whole fermentation period. However, they were slightly declined as the acidity increased. Those strains of leuconostoc, streptococci, pediococci and lactobacilli were identified as Luuconostoc mesenteroida subsp. musenteroides, Streptococcus fuecalzs, S, faeciurn, Pediococcus pentosaceus, Lactobacillus plarttarum, L. sake and L. brevis. Among lactobacilli, Id. sake and L. brmk, and L. plantarum were isolated mainly at the beginning and around the overripening period of fermentation, respectively.

• 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.

• Microbiology and Biotechnology Letters
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• v.27 no.4
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• pp.311-319
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• 1999

Leaves of Aloe vera Linne and bloods of domestic animal were composted in a soild state fermentation reactor (SSFR) by using microbial additive including a bulking and moisture controlling agent. From solid-culture of microbial additive, 10 species of bacteria and 10 species of fungi were isolated and, their enzyme activities including amylase, carboxy methyl cellulase CMCase, lipase and protease were detected. Optimum fermentation conditions of Aloe leaves and domestic animal bloods in SSFR were obtained from the studies of response surface analysis employing microbial additive content, initial moisture content, and fermentation temperature as the independent variables. The optimum conditions for SSFR using Aloe leaves were obtained at 9.45$\pm$73%(w/w) of microbial additives, 62.73$\pm$4.54%(w/w) of initial moisture content and 55.32$\pm$3.14$^{\circ}C$ of fermentation temperature while those for SSFR using domestic animal bloods were obtained at 10.25$\pm$2.04%, 58.68$\pm$4.97% and 57.85$\pm$5.$65^{\circ}C$, respectively. Composting process in SSFR was initially proceeded through fermentation and solid materials were decomposed within 24 hours by maintaining higher moisture level, and maturing and drying steps are followed later. After the fermentation step, the concentrations of solid phase inorganic components were increased while that of organic components were decreased. Also, concentrations of total organic carbon(TOC), peptides, amino acids, polysaccharides, and low fatty acids in water extracts were increased. As fermentation in composting process depends on initial C/N ratios in water extracts of two samples were increased because of increased water-soluble TOC. From these results, it was revealed that solid state fermentation reactor using microbial additives can be used in composting process of organic wastes with broad C/N ratio.

• Journal of Microbiology and Biotechnology
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• v.18 no.4
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• pp.711-717
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• 2008

To speed up the conversion of rice straw into feeds in a low-temperature region, a start culture used for ensiling rice straw at low temperature was selected by continuous enrichment cultivation. During the selection, the microbial source for enrichment was rice straw and soil from two places in Northeast China. Lab-scale rice straw fermentation at $10^{\circ}C$ verified, compared with the commercial inoculant, that the selected start culture lowered the pH of the fermented rice straw more rapidly and produced more lactic acid. The results from denatured gradient gel eletrophoresis showed that the selected start culture could colonize into the rice straw fermentation system. To analyze the composition of the culture, a 16S rRNA gene clone library was constructed. Sequencing results showed that the culture mainly consisted of two bacterial species. One (A) belonged to Lactobacillus and another (B) belonged to Leuconostoc. To make clear the roles of composition microbes in the fermented system, quantitative PCR was used. For species A, the DNA mass increased continuously until sixteen days of the fermentation, which occupied 65%. For species B, the DNA mass amounted to 5.5% at six days of the fermentation, which was the maximum relative value during the fermentation. To the authors' best knowledge, this is the first report on ensiling rice straw with a selected starter at low temperature and investigation of the fermented characteristics.

• Journal of environmental and Sanitary engineering
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• v.15 no.3
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• pp.24-30
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• 2000

In this study, to determine the optimum fermentation process for the feed production of food wastes and estimate the practical value of fermented feed using kudzu creeper and sawdust as bulking agent. This study considered initial C/N ratio control as the fermentation process variables. The result are summarized as follows. Minimum water contents of byproducts in the fermentation feed production showed 39%(kudzu), 37%(sawdust) at the C/N ratio 25 and 45%(kudzu, sawdust) at the C/N ratio 35. Temperature variations in the fermentation feed production at the C/N ratio 25 indicated $68^{\circ}C$(kudzu), $70^{\circ}C$(sawdust). Optimum condition of fermentation process of water content, C/N ratio and permeability (porous structure of the mixture). For optimum fermentation gravitationally dewatered garbage, the proper mixing ratios of kudzu(moisture contents : 17.3%) and sawdust(moisture contents : 13.2%) were 41% and 39%, respectively. Major biological reaction in the aerobic fermentation feed production occurred during 12~24hrs.

• Food Science and Biotechnology
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• v.16 no.6
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• pp.924-927
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• 2007

This study addresses the quality characteristics of commercial baechukimchi by analyzing its physicochemical characteristics and sensory properties in relation to fermentation time and temperature. The salinity of baechukimchi increased to 3.01% after 45 days of fermentation at 2 and $5^{\circ}C$, but decreased to 2.81% by 105 days. The pH decreased gradually at the beginning of fermentation, but decreased after 45 days. The acidity differed most between kimchi fermented at $2^{\circ}C$ (0.36%) and $5^{\circ}C$ (0.48%) at 45 days of fermentation. The vitamin C content was 8.47 mg% in kimchi fermented at both 2 and $5^{\circ}C$ on the day of initial production, then peaked after 45 to 60 days at 14.10 mg%, and decreased thereafter. The total microbial count gradually increased during the first 75 days of fermentation. The appearance and overall acceptability of baechukimchi were highest after 90 days of fermentation at $2^{\circ}C$ and after 60 days of fermentation at $5^{\circ}C$.

• Preventive Nutrition and Food Science
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• v.14 no.2
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• pp.156-161
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• 2009

Effects of extrusion conditions (barrel temperature and moisture content) and fermentation time on the antioxidant properties of root hair of tissue cultured raw mountain ginseng (MG) were investigated. The barrel temperature/ moisture combinations were: $110^{\circ}C$/25% (MG1), $140^{\circ}C$/25% (MG2), $110^{\circ}C$/35% (MG3) and $140^{\circ}C$/35% (MG4). Red ginseng (RG) was also investigated. The contents of 2,2-diphenyl-1-picrylhydrazyl (DPPH) and polyphenolic increased after fermentation in RG and even more in MG, while extruded ginseng samples exhibited little change. The increases noted with MG and RG occurred during the first 4 days of fermentation. DPPH radical scavenging activity decreased after extrusion and was significantly higher in MG (20.93%) than RG (1.63%) on the first day of fermentation. DPPH radical scavenging activity in the barrel temperature/moisture combinations were 19.01% (MG1), 14.45% (MG2), 20.37% (MG3) and 15.78% (MG4). The content of polyphenolic compounds in ginseng samples displayed a similar trend. Acidic polysaccharide in RG and MG1${\sim}$MG4 were higher than MG, but decreased during fermentation. Crude saponin in RG and MG1${\sim}$MG4 decreased after 15 days of fermentation, while increasing in MG.

• KSBB Journal
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• v.27 no.4
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• pp.251-256
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• 2012

In this study we investigated the effect of temperature on the two-stage fermentation of Makgeolli using uncooked germinated black rice. The fermentation processes were conducted at $15^{\circ}C$ for three weeks and $25^{\circ}C$ for 7 days. The pH of Makgeolli at $25^{\circ}C$ increased from pH3.0 to pH 4.2, which was consistent with that at $15^{\circ}C$. In contrast total acidity of Makgeolli at $15^{\circ}C$ was about half of that at $25^{\circ}C$ (0.36% and 0.59%, respectively). By the 7 days-fermentation at $25^{\circ}C$, 11% of alcohol was produced, whereas three weeks were required for the same alcohol production at $15^{\circ}C$. In the case of sugar contents, the amounts of total glucose-equivalent reducing sugars and glucose increased at the end of the fermentation at $25^{\circ}C$ up to 2.25 mg/mL and 3.4 mM, respectively, whereas those at $15^{\circ}C$ were maintained at very low levels (0.18 mg/mL and 0.1 mM, respectively). Such limited supplement of sugars at $15^{\circ}C$ seemed to affect metabolism of yeast, resulting in different composition of organic acid. At $25^{\circ}C$, citric acid that was 73.4 ppm at the initial fermentation was consumed completely, whereas 20 ppm of citiric acid was remained at $15^{\circ}C$. In addition, acetic acid and lactic acid in Makgealli at $15^{\circ}C$ were 53% and 14% of those at $25^{\circ}C$.

• Korean Journal of Microbiology
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• v.11 no.4
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• pp.167-174
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• 1973

This study included two parts of investigation, the microfloral changes during the brewing process with the changes of pH, total acidity, temperature and alcoholic contents, as well as determination of survival times of major enteric pathogens in Takju. 1. Maximum number of Saccharomyces cerevisiae was $4.3{\times}10^7$ per milliliter on the 5th day of fermentation and gradually decreased. Saccharomyces cerevisiae was one of the predominant strains of the fermentation process. The number of Saccharomyces cerevisiae was $4.3{\times}10^6$ per milliliter at the completion of the brewing and human consumption. In a few days after the completion of the brewing. Bacillus subtilis and some species of Staphylococcus spp. began to grow and those organisms were responsible for the spoilage. 2. Maximum pH, during the brewing, was 5.8 on the first day of fermentation and rapidly decreased until 6th day of fermentation at pH 4.3. 3. Maximum alcholic content was 14.5 degree on the 4th day of fermentation, 10.3 degree on the 5th day and this degree was continued during the experimentation. 4. Maximum temperature, during Takju brewing was 34.deg.C on the 3rd day of fermentation and rapidly decreased up to 23.deg.C on the 6th day and this temperature was continued until the brewing process was finished. 5. Maximum total acidity was 0.57 percent on the 4th day of fermentation and gradually decreased by brewing process was completed. 6. Survival time of major enteric pathogenic bacteria in Takju was as follows : Shigella dysenteriae and Escherichia coli were isolated in two hours and 14 hours respectively, but Salmonella typhi, Vibrio parahemolyticus were not isolated even in an hour after the inoculation of those organisms in undiluted Takju. In diluted Takju, Salmonella typhi, Vibrio parahemolyticus were not isolated even in an hour after the inoculation of those organisms in undiluted Takju. In diluted Takju, Salmonella typhi, Shigella dysenteriae, and Escherichia coli were survived for 50-60 hours, but Vibrio cholerae and Vibrio parahemolyticus were not isolated even if treated within one hour.

• Journal of Food Hygiene and Safety
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• v.32 no.1
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• pp.27-34
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• 2017

Effect of salt concentration (10, 20 and 30%, respectively) and fermentation temperature (10 and $20^{\circ}C$, respectively) on changes in quality index (VBN, Histamine, Amino nitrogen, Total viable cell counts, Coliform bacteria and E. coli counts) of culinary salted and fermented anchovy during fermentation were investigated to suggestion of fundamental documents for industrial objectives. Our results show that the effect of salt concentration on changes in quality index was not high compared with fermentation temperature in salted and fermented anchovy with below 20% of salt concentration however effect of salt concentration and fermentation temperature on quality index was not significant with 30% salt concentration. And all most whole changes of quality index were rapidly increased or decreased for 30 days of fermentation.