• Korean Journal of Microbiology
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• v.51 no.1
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• pp.21-30
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• 2015

The goal of this study was to identify relationships between the composition of sulfate reducing bacterial assemblages and terminal restriction fragment length polymorphism (T-RFLP) patterns in rice paddy and dry farming soils. Samples of organic farming soils, conventional farming soils, and dry field farming soils were collected in August and November. Analyses of the soil chemical composition revealed similar total nitrogen, total carbon and total inorganic phosphorus levels; however, the moisture content and total carbon were higher than in the other soils in both August and November, respectively. Sulfate reducing bacteria utilizing lactic acid were more widely distributed than those that used acetic acid, and the number of sulfate reducing bacteria in organic farming soil was most abundant. Phylogenetic analysis based on 181 clones revealed that most showed low similarity with cultured sulfate reducing bacteria, but more than 90% similarity with an uncultured sulfate reducing bacteria isolated from the environment. T-RFLP analysis revealed that fragments of 91, 357, 395, and 474 bp were most common, and the community structure of sulfate reducing bacteria changed seasonally.

• 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.

• 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).

• Journal of the East Asian Society of Dietary Life
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• v.15 no.4
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• pp.405-412
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• 2005

Quality characteristics of squid-sikhae prepared by four different methods(SHM: sikhae method, SHM-LA; sikhae method added with L plantarum, MM; mixed method of sikhae method and salting method, MM-LA; MM method added with L plantarum) were investigated during fermentation at $20^{\circ}C$. The pHs of all the 6-days fermented sikhae samples were in the range of 4.01-3.76, meaning that there were no significant difference in pH according to the preparation methods. Number of total microbes(TM) were decreased, while the ratio of lactic acid bacteria against TM in SHM-LA and MM-LA was higher than those of SHM and MM. There were no differences in acid protease activity, while $NH_2-N$ content of SHM and MM were higher than those of SHM-LA and MM-LA. Amylase activity was the lowest in MM-LA. Proteins separated by SDS-PAGE belonged to 7-200 kDa, the major proteins (153<94<41 kDa) of the sikhae in all plots were disappeared at 6 days fermentation. In sensory evaluation, sour taste of MM was the highest, while it was the lowest in SHM-LA. Sweet taste, bitter taste, salty taste and hot taste were not significantly different Off-flavor was decreased in lactic acid bacteria added products. Scores of the softness and overall acceptability were the highest in SHM-LA. These results indicated that SHM-LA was the best method for the preparation of squid sikhae because of the enhancement of lactic acid fermentation and overall acceptability.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.5
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• pp.747-753
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• 1996

This study was undertaken to enhance the shelf-fife of kimchi by heat treatment at $40~80^{\circ}C$ for Chinese cabbage during salting. Kimchi was analyzed to determine pH, titratable acidity and sensory evaluation, number of microbe and lactic acid bacteria, content of organic acid and texture. The kimchi(HT 40-kimhi) soaked with Chinese cabbage by heat treatment at $40^{\circ}C$ was enhanced the shelf-life more than that of control kimchi when evaluated by pH, titratable acidity, sour taste and overall taste. HT 40-kimchi was higher in hardness and the lowest in brittleness and gumminess and also, the content of lactic acid, number of total microbe and lactic acid bacteria were the lower than those of control kimchi. Considering all results obtained throughout these experiments, it can be concluded that the kimchi soaked with Chinese cabbage salted in heated 10% salt solution at $40^{\circ}C$ improved the quality and shelf-life of kimchi.

• Korean Journal of Food Science and Technology
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• v.30 no.4
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• pp.948-956
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• 1998

This study aimed to investigate of Andong sikhe by using pure culture inoculation technique and the improvement of storage stability by the addition of stabilizers to the product. Microorganisms were selected for the pure culture inoculation in the fermentation. The changes in chemical composition such as total acidity, sugar content, amino acid and various forms of nitrogen during fermentation were determined. The changes in pH of the product, the enzyme activities and the population of lactic acid bacteria and yeast were also followed in the process of fermentation.

• Journal of the Korean Society of Food Culture
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• v.24 no.1
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• pp.90-95
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• 2009

The principal objective of this study was to investigate the influence of buckwheat sprouts on the acid production and growth of lactic acid bacteria in to which 5 and 10%(w/v) buckwheat sprouts was added, followed by fermentation with Lactobacillus bulgaricus. In yogurt to which 5 and 10% buckwheat sprouts was added, pH was lower and titratable acidity was higher than those of the control. It was also noted significant changes in the number of viable cell counts with differing amounts of added buckwheat sprouts until 12 hours. When the yogurt samples were stored for 12 days at $4^{\circ}C$, the pH and titratable acidity of the yogurt to which 5 and 10% buckwheat sprouts was added were maintained at lower and higher than control levels, respectively. The highest number of viable cell counts was found in the yogurt to which 5% buckwheat sprouts was added. Rutin content was reduced via lactic acid fermentation, but quercetin content increased significantly in the yogurt with added buckwheat sprouts. It may be that the glycosidic bonds connected to rutin were hydrolyzed during fermentation by lactic acid bacteria. The total phenol compound content of the yogurt samples also increased after fermentation. The antioxidative activity of yogurt to which 10% buckwheat sprouts was added was shown to have a 60.95% free radical scavenging effect, which was the highest among all yogurt samples evaluated.

• Korean Journal of Food Science and Technology
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• v.22 no.4
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• pp.373-379
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• 1990

Lactic acid bacteria(LAB) were isolated from fermenting Kimchi and were cultivated in filter-sterilized Chinese cabbage juice individually or in combination. LAB isolated were Lactobacillus leichimannii, Lac. fermentum, in addition to the already known Leuconostoc mesenteroides, Lac. plantarum, lac. brevis and pediococcus pentosaceus. Lac. leichimannii, Lac. fermentum and Lac. sake, the early lactobacilli, were high in number exceeding $10^4cells/ml$ at 0 time and multiplied up to $10^9cells/ml$ altogether at the 3rd day of kimchi fermentation. When the representative LAB were cultivated singly in Chinese cabbage juice with or without 3.0% NaCl, one strain of Leu. mesenteroides and La. leichmannii were not different in acid producing ability while the other strain of Leu. mesenteroides and Lac. fermentum Lac. plantarum, produced less acid when NaCl was present. When the bacteria in combination were cultivated in Chinese cabbage juice with 3.0% NaCl, the presence of Leu. mesenteroides was essential to eliminate the lag phase in acid production with higher amounts of acid produced than without. The total number of lactobacilli in the mixture of kimchi ingredients was about $2.9{\times}10^4 cells/ml$ while the number of Lac. plantarum was 7.3 cells/ml. The number of Lac. plantarum in individual ingredients were normally in the range between $0.0{\sim}240cells/g$ except garlic sold in ready-to-use form with $9.0{\times}10^3 cells/g$.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.3
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• pp.240-244
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• 2006

To develop a health-aid preparation of Chinese yam (Dioscorea batatas Decne), lactic acid fermentation was attempted using a mixed starter comprising of Lactobacillus acidophilus, Streptococcus thermophilus, and Bifidobacterium bifidus. The anaerobic fermentation of a 5% Chinese yam flour suspension gave a uniform suspension of pH 4.35, containing $7.76{\times}10^6 CFU/mL$ lactic acid bacteria (LAB), and which was found to be acceptable to the panel from a sensory assessment. During the administration of the lactic acid fermented (LAF) Chinese yam to Sprague Dawley rats for 6 weeks, a smaller body weight gain, but greater excretion of feces were observed, implying the creation of a healthy gastrointestine on the administration of LAF Chinese yam, which was also confirmed by the gastrointestinal motility of the feed in rats fed on LAF Chinese yam. The constipation induced by loperamide was further suppressed in a rat group fed on a LAF Chinese yam diet, which was qualified from healthy gastrointestinal flora established by LAB. A serochemical analysis revealed a slight improvement in the blood glucose, neutral lipid and total cholesterol concentrations on administration of LAF Chinese yam, suggesting LAF Chinese yam could be served as a healthy-aid preparation, even for hyperglycemia or hyperlipidemia patients.

• Journal of Food Hygiene and Safety
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• v.35 no.3
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• pp.279-283
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• 2020

In this study we evaluated the antimicrobial effects of EcoCal^® (calcium oxide) and GF Bactostop^® (organic acids mix) in sausages during storage at 10℃. The sausages were formulated with 0.1% EcoCal^® (0.1ECO), 0.1% EcoCal^®+0.5% GF Bactostop^® (0.1ECO+0.5GF), 0.2% EcoCal^® (0.2ECO), and 0.2% EcoCal^®+0.5% GF Bactostop^® (0.2ECO+0.5GF). Total aerobic and lactic acid bacteria in the sausages were enumerated on tryptic soy agar and Lactobacilli MRS agar, respectively, during storage at 10℃ for 10 weeks. The 0.1ECO+0.5GF showed the most effective antimicrobial effects on the sausages, and 0.1ECO showed the second most effective antimicrobial effect. Total aerobic bacterial cell counts gradually increased in the control, 0.2ECO, and 0.2ECO+0.5GF groups, but cell growth was generally inhibited in 0.1ECO by approximately day 42 (P<0.05) and 0.1ECO+0.5GF by approximately day 49 (P<0.05). Lactic acid bacterial cell counts gradually increased in the control, 0.2ECO, and 0.2ECO+0.5GF groups, but the lactic acid bacteria growth was inhibited in 0.1ECO by approximately day 49 (P<0.05) and in 0.1ECO+0.5GF by approximately day 64. These results suggest that using 0.1% EcoCal^®+0.5% GF Bactostop^® in sausage formulation is useful for inhibiting lactic acid bacteria growth, thereby extending the shelf-life of the sausage product.