• The Korean Journal of Mycology
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• v.39 no.2
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• pp.151-153
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• 2011

In order to optimize storage conditions of Korean traditional Makgeolli, we brewed Korean traditional Makgeolli for 1 week with two-stage fermentations and investigated changes viable cell counts of yeasts and bacteria during storage for 1 month at $4^{\circ}C$ and $20^{\circ}C$. Yeast viable cell counts were decreased to 89.0% after storage for 30 days at $20^{\circ}C$, however, those were not significantly changed at $4^{\circ}C$ storage. Bacteria cell counts were decreased to 59.0% of initial cell counts for 30 days at $4^{\circ}C$. In the storage at $20^{\circ}C$, bacteria were significantly decreased to 98.0% of initial cell counts after storage for 30 days. Lactic acid bacteria were also similar to those of total bacteria cell counts at $4^{\circ}C$ storage, however, 99% of lactic acid bacteria were decreased at $20^{\circ}C$ storage for 30 days.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.6
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• pp.864-871
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• 2010

White and black garlic pastes were fermented by Leuconostoc mesenteroides and evaluated for its rheological and functional properties such as consistency, antioxidant and angiotensin converting enzyme inhibitory activity. The pH, acidity and solid content of black garlic paste were 4.60, 1.23%, 22.63%, respectively. The viable cell counts and consistency of fermented garlic was decreased by adding higher amounts of black garlic paste. Fermentation of white garlic (40%)/black garlic (10%) showed viable cell counts of $1.6\times10^{11}$, fluid consistency of 9.31 $Pa{\cdot}s^n$. Water and 70% ethanol extract from fermented garlic showed the polyphenol content of 6.29mg/mL and 5.99 mg/mL, respectively. Also, water extract indicated the DPPH radical scavenging effects and angiotensin converting enzyme (ACE) inhibitory activity with $IC_{50}$ 1.03 mg/mL and $IC_{50}$ 68.54 mg/mL, respectively. ACE inhibitory activity was increased with adding black garlic paste. Conversion of sucrose into dextran polymer in fermented garlic was drastically decreased by the addition of black garlic paste, indicating from 85% (0% black garlic) to 20% (20% black garlic) conversion yield. Garlic paste fermented with 10% black/40% white garlic showed the decrease in consistency and viable cell counts during both cold and freezing storages. In particular, consistency of fermented garlic was lower during freezing storage than cold storage, and the viable cell counts was drastically decreased after storage for 2 weeks.

• Journal of Food Hygiene and Safety
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• v.1 no.1
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• pp.47-50
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• 1986

Sanitary condition for raw milk in Korea was investigated in this study. It is hoped that the information will be used for reference in future endeavors of study in the field of public health and food sanitation in Korea. The results were summerized as follows: 1) The viable cell counts of bacteria in raw milk were tend to be increased under the various atmospheric temperature, and the correlation coefficient between temperature and total viable cells was r=+0.921(p<0.01). 2) The correlation coefficient between methylene blue reduction time test and viable cell counts of bacteria in raw milk was r=-0.799(p<0.01). 3) The relationship between total solid rate(%) and milk fat rate(%) was highly significant level as r=+0.745(p<0.01). 4) Highly significant correlation coefficient was r= +0.945(p<0.01) between milk fat and protein rate in raw milk.

• The Korean Journal of Food And Nutrition
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• v.13 no.1
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• pp.71-77
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• 2000

New type yogurt base were prepared from milk added with skim milk powder or purple sweet potato, and fermented by lactic acid bacteria (Streptococcus thermophilus and Bifidobacterium infantis, 1:1, v/v). The yogurt proudcts were evaluated for acid production(pH, titratiable acidity), number of viable cell, viscosity, sensory properties, and color value. The composition of some organic acids was also analyzed by GC. The acid production slightly decrerased by addition with purple sweet potato. There was no significant difference in viable cell counts between control (yogurt added with only skim milk powder) and yogurt added with purple sweet potato, and viable cell counts of all samples were above 9.08 log cfu/ml. Viscosity of yogurt added with purple sweet potato(36,800∼46,000 centipoise) was higher than that of yogurt added with only skim milk powder(32,200 centipoise). The overall sensory score of yogurt added with purple sweet potato(38.6%, dry base) was the best of tested yogurt. The major organic acid of yogurt added with purple sweet potato was lactic acid. its content was 0.997∼1.203%. malic acid, succinic acid, oxalic acid, and fumaric acid were analyzed out a little. Lightness and yellowness decreased by addition with purple sweet potato but redness increased. Total color difference($\Delta$E) with yogurt addition with purple sweet potato and only skim milk powder were very high(above 11.46).

• Microbiology and Biotechnology Letters
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• v.24 no.2
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• pp.247-253
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• 1996

Changes in microorganisms, enzyme activities and major components of two types of Doenjang prepared with spring Meju and autumn Meju and Kochujang were investigated during 4 months of fermentation. The viable cell counts of aerobic bacteria in Doenjang and Kochujang were increased up to 60 days of fermentation, but viable cell counts of anaerobic bacteria did not show remarkable changes during fermentation. Viable cell count of yeast showed a rapid increase up to 15 days of fermentation in Doenjang and 60 days in Kochujang. It was found that $\alpha$-amylase activity of autumn Meju Doenjang and glucoamylase activity of Kochujang were higher than the other. Acidic and neutral protease showed the highest activity during 15-30 days of fermentation. The pH of Doenjang was increased up to pH 7.0 until 60 days of fermentation, but pH of Kochujang gradually decreased during fermentation. Moisture content of spring Meju Doenjang and Kochujang decreased to 40% during ferme- ntation and reducing sugar content of Kochujang increased up to 15 days of fermentation, but decreased after that.

• The Korean Journal of Food And Nutrition
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• v.21 no.2
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• pp.176-183
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• 2008

This study examined the anti-microbiological effects of chlorine treatment on the surface of fresh fruits, in order to improve microbiological safety in school foodservice operations. Non-peeled fruit(strawberries) and peeled fruit(bananas) were treated with different concentrations of chlorinated water and rinsing numbers, followed by microbiological testing. The fruits were immersed at different concentrations of chlorinated water(0 ppm, 50 ppm, and 100 ppm) and durations(3 min and 5 min), and were then rinsed with tap water(one time, two times, or three times). The total viable cell counts of both the strawberries and bananas ranged from $10^3$ CFU/g to $10^4$ CFU/g, and coliform levels ranged from $10^2$ CFU/g to $10^3$ CFU/g. As the chlorine concentration, immersion time, and rinsing number increased, anti-microbiological activity increased. The largest microbial reduction was shown with immersion for 5 min in 100 ppm chlorinated water and three rinsings. In the strawberries, this treatment reduced the initial population of total viable cells and coliforms by 3.29 log CFU/g and to an undetectable level, respectively, no total viable cells or coliforms were detected on the banana surface following this treatment. However, after a sterilization treatment with immersion for 5 min in 50 ppm chlorinated water and three rinsings, the total viable cell counts and coliform counts of the strawberries and bananas decreased to acceptable levels, based on the microbiological standards for ready-to-eat foods. Overall, it was shown that the sterilization treatment of 50 ppm chlorinated water, soaking for 5 min, and three rinsings provided an effective reduction in surface microbes, and enhanced the microbiological safety of the fruit.

• KSBB Journal
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• v.18 no.1
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• pp.14-18
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• 2003

In this study of the simultaneous saccharification and fermentation (SSF) of paper sludge, fed-batch cultivation of Lactobacillus paracasei subsp. paracasei KLB58 was attempted to produce viable KLB58 cells and lactic acid. Optimal culture conditions, including the temperature and concentration of the supplemented enzyme, were examined in terms of lactic acid production and viable cell count. When the effects of culture temperature and $\beta$-glucosidase concentration were examined in fed-batch SSF, the highest viable cell counts and lactic acid production (i.e. 5$\times$$10^9$ CFU/ml and 45 g/L, respectively) were obtained at 37$^{\circ}C$ and 2 unit/ml of $\beta$-glucosidase.

• Food Science and Biotechnology
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• v.16 no.2
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• pp.198-204
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• 2007

The objectives of this study were to determine the quality characteristics, antioxidant activity, and cytotoxicity of fermented ginseng wine at each fermentation step. In the first mash with and without ginseng, viable cell counts (total cell, lactic acid bacteria, and yeast) were maximum between 2 to 4 days of fermentation. At the beginning of fermentation, Brix and ethanol contents, and titratable acidity increased, while pH decreased rapidly. At 3 days of fermentation of the second mash with ginseng, the viable cell counts were similar to those without ginseng and then continually decreased. At the end of fermentation, the pH of the second mash with ginseng was 4.00, lower than the pH of the second mash without ginseng, which was 4.35. Alcohol contents of second mashes with and without ginseng were 12.2 and 11.8%, respectively. In the aging period of ginseng and rice wines, the pH, titratable acidity, Brix, and ethanol contents did not change markedly. The results of sensory evaluation showed that fermented ginseng wine had good flavor and high acceptability. In the 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity assay, fermented ginseng wine ($IC_{50}$: 0.394 mg/mL) showed higher antioxidant activity than fermented rice wine ($IC_{50}$: 0.884 mg/mL). The butanol fraction of fermented ginseng wine exhibited weak cytotoxic activity against P388 and HeLa cell lines.

• Microbiology and Biotechnology Letters
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• v.40 no.2
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• pp.111-116
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• 2012

In this study, we investigated the microbial flora changes in Gugija-Liriope tuber Makgeolli during fermentation and storage periods. We brewed Gugija-Liriope tuber Makgeolli for a week through twostage fermentations and stored the fermentation broth for a month at $4^{\circ}C$ or $20^{\circ}C$. We collected the samples periodically and analyzed microbial flora changes using viable cell counts and PCR-denaturing gradient gel electrophoresis (DGGE). Yeast viable cells were seen to have decreased to 13% of pre-storage levels after storage for 15 days at $20^{\circ}C$; however significant changes were not observed during storage at $4^{\circ}C$. Prolongation of storage time dramatically decreased the availability of viable cells. Yeast viable cell numbers had decreased to 38% of pre-storage levels at $4^{\circ}C$ and 4.8% at $20^{\circ}C$ after storage for 30 days. The results of the DGGE profile for yeast showed that Saccharomyces cerevisiae and Saccharomyces sp. were the predominant strains at the beginning of fermentation and throughout the whole period of storage. Viable cell counts for total bacteria had decreased to 36% of pre-storage levels after storage for 15 days but did not significantly change for the full 30 days of storage at $4^{\circ}C$. Similarly, viable cell counts for bacteria had decreased to 5% while viable cell numbers did not significantly change for the full 30 days at $20^{\circ}C$. Viable cell counts for lactic acid bacteria were performed and the results were similar to those for total bacteria. The results of the DGGE profile for bacteria showed that Weissella cibaria was the predominant strain at the beginning of fermentation. However it had disappeared by the end of fermentation, and Lactobacillus fermentum and Pediococcus acidilactici became the predominant species during storage.

• Journal of Microbiology and Biotechnology
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• v.25 no.12
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• pp.2049-2057
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• 2015

Various salt concentrations (1.0%, 1.3%, 1.6%, 1.9%, and 2.1% labeled as sample A, B, C, D, and E, respectively) were investigated for microbial diversity, identification of Lactic Acid Bacteria (LAB) in salted kimchi cabbage, prepared under laboratory conditions. These samples were stored at 4°C for 5 weeks in proper aluminum-metalized pouch packaging with calcium hydroxide gas absorber. A culture-independent method known as polymerase chain reaction - denaturing gradient gel electrophoresis was carried out to identify LAB distributions among various salt concentration samples that had identified 2 Weissella (W. confusa and W. soli), 1 Lactobacillus (Lb. sakei), and 3 Leuconostoc (Lc. mesenteroides, Lc. lactis, and Lc. gelidum) in the overall kimchi samples. The pH, titratable acidity, viable cell counts, and coliform counts were not affected by salt variations. In order to assess sensory acceptance, the conducted sensory evaluation using a 9-point hedonic scale had revealed that samples with 1.3% salt concentration (lower than the manufacturer's regular salt concentration) was more preferred, indicating that the use of 1.3% salt concentration was acceptable in normal kimchi fermentation for its quality and safety. Despite similarities in pH, titratable acidity, viable cell counts, coliform counts, and LAB distributions among the various salt concentrations of kimchi samples, the sample with 1.3% salt concentration was shown to be the most preferred, indicating that this salt concentration was suitable in kimchi production in order to reduce salt intake through kimchi consumptions.