• Food Science of Animal Resources
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• v.28 no.5
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• pp.587-595
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• 2008

In order to develop a new starter for fermented milk, 1037 bacterial strains were isolated from raw milk. The strain that showed excellent acid producing and angiotensin converting enzyme (ACE) inhibitory activity (88.6%) was selected and identified as a Lactobacillus zeae based on the result of API carbohydrate fermentation pattern and 16S rDNA sequence. Lactobacillus zeae RMK354 was investigated further to study its physiological characteristics. It showed strong ACE inhibitory activity compared with commercial LAB starters tested. The optimum growth temperature of L. zeae RMK354 was $40^{\circ}C$ and it took 10 hr to reach pH 4.3 under this condition. L. zeae RMK354 showed more sensitive to penicillin-G, bacitracin, novobiocin, in a comparison of 14 different antibiotics, and showed most resistance to polymyxin B and vancomycin. It showed higher esterase and leucine arylamidase activities compared with 16 other enzymes. It was comparatively tolerant to bile juice and able to survive at pH 2 for 3 hr. It showed inhibitory activity against Salmonella Typhimurium with the rate of 60%. Based on these and previous results, L. zeae RMK354 could be an excellent starter culture for fermented milk with high level of ACE inhibitory activity.

• Culinary science and hospitality research
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• v.22 no.5
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• pp.117-133
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• 2016

This study was to investigate the quality characteristics of sourdough bread made with 4 kinds of kamut sour starter. Kamut sour starters were made according to dough yield of sour starter and yeast adding on sour starter. We exmanined pH level, fermentation rate, specific volume, CrumbScan, moisture content, color value, texture analyzer, shelf-life test and sensory evaluation for observing quality characteristics of sourdough bread. From the results of pH measurement, kamut sourdough breads had lower pH value in dough and crumb pH than CON. In the experiment of dough's fermentation rate, CON had the rapidest fermentation rate among the samples initially, but the experimental groups also expanded as much as CON grew in spite of its slow fermentation. Specific volume and CrumbScan results suggested that CON had the largest volume. In addition, CM and TM had smaller volume than Pool and Biga. The sample that had the highest moisture content was Pool because its sour starter had the most amount of water. In color value test, CON had lighter crumb and crust color than other specimens. As a result of the TPA and shelf-life tests, CON had the softest hardness after 24 hours. However, Pool had similar hardness with CON after 72 hours. The result of the acceptance test of sourdough breads indicated that people prefered Pool and Biga to TM and CM. Difference test showed similar results with prior experiments. As the final outcome, Poolish was chosen as the optimal formula for kamut sour starter.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.8
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• pp.1245-1252
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• 2003

A starter formulation was developed to substitute a baker's yeast with natural starter when manufacturing bread products. To develop an active starlet, starter was formulated varying with types of wheat flours, level of water contents and various nutrients. Activities of starter were investigated in terms of viable counts of microbes and change of pH and total titratible acidity Domestic wheat flours contain 100 times more number of lactic acid bacteria than yeast regardless of types of wheat flours. The more protein contents in wheat flours, the more stable microbes in starter. This was considered to be the result of buffering effect of wheat proteins. The optimum level of protein content to ensure the activity of starter was more than 12.0%. Optimum level of water content in active starter was 110% based on strong flour. The more water or the less water had the tendency of decreasing viable counts of microbes. Addition of salt and sucrose had increased the activity of starters. However oligosaccharides did not affect the activity of starter. The optimum concentrations of salt and sucrose were 1.0% and 5.0% respectively. Bread with the starter was higher scored than breads with yeast in terms of all the quality and sensory characteristics except their volumes. In conclusion, a starter formulated with strong flour 100%, water 110%, salt 1% and sucrose 5% was considered to have high potential as a substitute of yeast in making natural bread.

• Korean Journal of Microbiology
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• v.50 no.4
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• pp.319-326
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• 2014

Two bacterial strains, named as LE17 and LE22, were isolated from traditionally fermented soybean products in order to select lactic acid bacteria for the reduction of biogenic amines and harmful bacteria. Both strains were identified as Pediococcus pentosaceus by 16S rRNA sequence analysis and additional biochemical tests. The strain LE17 reduced the amines by 13.7% for histamine and by 25.9% for tyramine, when it grew in minimal synthetic media containing 0.1% (w/v) histamine and 0.1% tyramine at $30^{\circ}C$ for 48 h, while the strain LE22 reduced the amines by 23.7% for histamine and by 15.7% for tyramine. Both strains also had broad inhibition spectra against pathogens. Considering their properties, they could be used as starters for industrial soybean fermentation.

• The Korean Journal of Mycology
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• v.42 no.4
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• pp.282-288
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• 2014

In this study, we attempted to isolate fungi from soybean fermented foods produced in Sunchang County and to identify Aspergillus oryzae from fungal isolates. Ten fungal isolates were identified with ${\beta}$-tubulin gene. According to the sequences of ${\beta}$-tubulin gene, ten fungal isolates were identified as A. oryzae/flavus complex. For further identification of the ten of fungal isolates, omtA gene, one gene of the aflatoxin biosynthesis gene cluster, was sequenced and the sequences were compared with those of A. oryzae and A. flavus strains from the GenBank database. In addition, identification of the ten fungal isolates was further confirmed using the PCR amplicon of norB and cypA intergenic region, in which a deletion was recognized relative to A. flavus and A. parasiticus. The amplicon size of the ten fungal isolate strains was smaller than those of A. flavus and A. parasiticus, but the same as that of the reference A. oryzae strain. These results indicated that the ten isolates should be identified as A. oryzae. The protease activity in rice koji made with 6, 13, 17, 27, 37 and 38 of strain, respectively was twice higher than that in control. The kojis made with nine of the A. oryzae isolates, respectively, did not produce aflatoxin, suggesting that the strains could possibly be used as starters for soybean products.

• Korean Journal of Microbiology
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• v.42 no.2
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• pp.160-163
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• 2006

Brown rice contains rice bran and germ with higher nutritional value and dietary fiber content compared with the polished rice. However, brown rice has a limitation of poor digestion. fermented brown rice could be better nutritional source and improve digestibility. Therefore, we tried to select good fermentative microorganisms which have nutritional values with high amylase and protease activities, and probiotic effects. Nineteen micro-organisms, including eight Bacillus strains isolated from Chongkukjang and 11 lactic acid bacteria, were screened for the fermentation ability and enzyme production. The liquid broths containing 2.5%(w/v) of raw brown rice powder as a sole nutritional source were used for culture media. Among the strains tested, all of the Bacillus strains and two lactic acid bacteria (Leuconostoc gelidum and Pediococcus pentosaceus) showed increase in cell population and enzyme activities. The viable cell counts of all the Bacillus strains and two lactic acid bacteria exceeded $10^7 CFU/mL$. The maximal enzyme activities produced by Bacillus sp. Bl, Bacillus sp. B2, Bacillus sp. B11, L. gelidum and P. pentosaceus were 17.85, 17.50, 17.10, 17.10 and 3.24 U/mL for amylase and 22.48, 22.04, 23.76, 12.13, and 3.4 U/mL for pretense, respectively. Therefore, the results of this study demonstrated that the above strains could be potential starters for the fermentation of raw brown rice.

• Journal of the Korean Society of Food Culture
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• v.20 no.3
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• pp.337-340
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• 2005

Fourteen strains out of fifty six strains of lactic acid bacteria isolated from Kimchi showed a resistance to artificial gastric juice. In particular, lactobacilli AK 3, AK 7, BK 28, and DK 37 showed a strong resistance and their viable cell counts of the initial stage were no change after the 2 hours cultivation in an artificial gastric juice. All five lactic acid bacteria were used as starters in producing yogurts. The physicochemical characteristics of yogurts were examined. The original pH, titratable acidity, visicosity and viable cell counts of yogurts were $3.78{\sim}4.32,\;0.96{\sim}1.41%,\;1,659{\sim}2,348\;cps\;and\;1.1{\times}10^9{\sim}2.1{\times}10^9cfu/mL$, respectively. The ${\beta}-galactosidase$ activity reached maximum at 48 hr, and reduced gradually during incubation.

• Food Engineering Progress
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• v.14 no.4
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• pp.292-298
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• 2010

Wheat germ contains the glycosylated forms of 2-methoxy-p-benzoquinone (2-MBQ) and 2,6-dimethoxy-p-benzoquinone (2,6-DMBQ), both of which have antimicrobial and immunostimulatory effects. Conversion of glycosylated 2-MBQ and 2,6-DMBQ to their more functional unglycosylated forms requires enzymatic action of $\beta$-glucosidase. We investigated the applications of lactic acid bacteria and yeast that produce $\beta$-glucosidase as starters for production of unglycosylated 2-MBQ and 2,6-DMBQ from wheat germ. Lactobacillus zeae and Pichia pijperi were selected through $\beta$-glucosidase enzyme assays for 37 yeast strains and five strains of lactic acid bacteria. Lb. zeae was more efficient than P. pijperi at producing 2-MBQ and 2,6-DMBQ from wheat germ. After 48 hr of fermentation with a mixed culture of Lb. zeae and P. pijperi, the concentration of 2-MBQ was 0.46${\pm}$0.07 mg/g, indicating an approximately 1.6-fold higher concentration than that obtained by pure culture of Lb. zeae. However, the concentration of 2,6-DMBQ was not significantly enhanced by fermentation with a mixed culture of Lb. zeae and P. pijperi.

• The Journal of the Convergence on Culture Technology
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• v.5 no.3
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• pp.125-130
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• 2019

This research is about alternative measure of main components for sprinkler system like automatic wet pipe sprinkler system, dry pipe sprinkler system, pre-action sprinkler system, vacuum sprinkler system, deluge sprinkler system, and so on. By replacing the alarm check valve, dry valve, pre-operated valve, and deluge open valve with a solenoid valve, it be can be simplifed the various processes of the manufacturing process into one process, it creates an environment in which one standardized product can be produced simultaneously on a single machine. Therefore, it could improve the price competitiveness of products, reduce the maintenance cost, and help the adaptability of new sprinkler systems in the future. There is a benefit when it comes to apply to sprinkler system. Only replace the valve which is used to control primary and secondary valve such as wet, dry, pre operated, vacuum, deluge system valve. Other components such as retarding chambers, automatic air compressors, accelerators or adjusters, supervisory panels, vacuum pumps, and manual starters can be used as they are, so they can be easily applied to existing sprinkler system. It is needed to legal and institutional study for solenoid valve applied sprinkler system to commercialize.

• Microbiology and Biotechnology Letters
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• v.49 no.2
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• pp.255-263
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• 2021

In this study, we assessed the technological characteristics and safety of 88 Enterococcus faecium strains isolated from meju; the strains possess the glutamate decarboxylase gene gadA/B involved in γ-aminobutyric acid production. The study was conducted to evaluate the possibility of introducing E. faecium meju isolates as food fermentation starters. We observed that a NaCl concentration of 6% (w/v) facilitated the growth and acid production of all strains. At a NaCl concentration of 7%, 21 strains (24%) exhibited a low growth rate, 72 strains (82%) a weak acid production, and 16 strains (18%) showed no acid production. All strains exhibited protease activity at a NaCl concentration of 4%. At a NaCl concentration of 5%, 86 strains exhibited weak activity, and one strain showed no protease activity. We could not detect any lipase activity in the investigated strains. None of the strains exhibited an acquired antibiotic resistance to the seven antibiotics tested in the present study, namely ampicillin, chloramphenicol, ciprofloxacin, gentamicin, penicillin G, tetracycline, and vancomycin. We could identify the Enterococcus endocarditis antigen gene efaA and the tyrosine decarboxylase gene tdc contributing to tyramine production, in 88 meju isolates. We could not detect the Enterococcus surface protein gene esp, which is specifically possessed by human-originated E. faecium strains, in any of the 88 strains tested in the study.