• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.5
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• pp.765-769
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• 2002

Improvement of hygienic quality of powdered raw grains and vegetables by fermentation was investigated. Luc-tobacillus sp. isolated from kimchi was used as a starter. The cell counts of coliform group and SS enteric bacteria on the SS agar plate in raw grains and vegetables were 2.3$\times$103 cfu/mL and 8.6$\times$10$^3$ cfu/mL, respectively. The starlet, Lactobacillu sp., reached 10$^{7}$ cfu/mL after 48 hr in fermentation. At that time, the coliform group and enteric bacteria on the SS agar plate were gradually inactivated and eliminated after 60 hr of fermentation. During the fermentation process, pH of the suspension was lowered and acidity increased. Antimicrobial activity of the acidic supernatant of fermented raw grains and vegetal]les against the E. coli sp. and Salmonella sp. was higher than that of lactic acid solution or neutralized supernatant. Therefore, it was considered that antimicrobial effect of the fermented raw grains and vegetal]les might be accelerated by tile synergic effect of acid and bacteriocin, and liquid fermentation of powdered raw grains and vegetables will be effective for inactivation of hygienic microorganisms.

• Korean Journal of Food Science and Technology
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• v.46 no.1
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• pp.115-120
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• 2014

The purpose of this study was to develop a rice straw-derived Bacillus cereus (B. cereus)-free starter culture for traditional soybean fermented products using a B. cereus-specific bacteriophage, BCP8-2. To determine the optimal medium that supports the growth of rice straw-derived microorganisms and BCP8-2 activity, 5 different culture media were tested. The 5% ground bean (GB) medium was selected for further study. No B. cereus was detected in the BCP8-2-treated rice straw in GB medium, whereas B. cereus at a level of $10^7$ CFU/mL was recovered in the no-phage control. The total bacterial count reached approximately $10^9$ CFU/mL regardless of phage addition. When the 16S rRNA sequence-based microbial community was monitored using denaturing gradient gel electrophoresis (DGGE) and pyrosequencing, a similar microbial community was observed in the phage-treated and control samples. In conclusion, we demonstrate that phage can be used to prepare a rice straw-derived B. cereus-free starter culture with minimal effect on natural microflora.

• Food Science and Biotechnology
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• v.17 no.5
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• pp.940-946
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• 2008

In the development of a nutrient enhanced functional food, kimchi was produced by using high $\gamma$-aminobutyric acid (GABA) producing lactic acid bacterium as a starter strain. The strain isolated from kimchi was identified by using an API kit and named Lactobacillus sp. OPK 2-59. Kimchi was produced by 3 methods 1) monosodium glutamate (MSG) added (M group); 2) starter added (S group); 3) MSG+starter added (M&S group). The produced kimchi was fermented for 24 hr in an incubator at a temperature of $15^{\circ}C$ and stored at $0-1^{\circ}C$ to examine its characteristics. The M&S group exhibited a sharper increase in acidity and a steeper fall in pH as well as a higher number of lactobacilli. The M&S group kimchi had 18 mg/100 g (fresh weight, f.w.) of GABA, whereas the M and S group each had 6 mg/100 g (f.w.) GABA. According to functional evaluation, the M&S group kimchi, which has higher GABA, was not significantly different in taste, color, texture, or smell, but the M&S group was generally superior. In summary, using Lactobacillus sp. OPK 2-59 and MSG, a high quality kimchi with increased GABA content can be produced as a functional food.

• Korean journal of food and cookery science
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• v.16 no.4
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• pp.358-362
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• 2000

To investigate the effect of sourdough on the quality characteristics of barley bread, sourdough starlet with Lactobacillus plantarum, Lactobacillus sanfrancisco and Enterococcus mundtii was used for baking after 48 hours incubation at 37$\^{C}$. The specific volume of the bread containing sourdough starter was greater than that the control. Retarding of the firmness was observed in the bread with Lactobacillus sanfrancisco compared with the control and other breads. Above results suggest that sourdough starter fermented by Lactobacillus can be used as natural bread improver.

• Journal of Microbiology and Biotechnology
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• v.3 no.3
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• pp.199-203
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• 1993

The bacteriocin produced by Pediococcus acidilactici KFRI 168 exhibited a wide antimicrobial spectrum including many strains of lactic acid bacteria, Listeria monocytogenes, Staphylococcus aureus, and Enterococcus faecium by both disk and deferred assay methods. Inhibition of Lis. monocytogenes and Stph. aureus were observed only from deferred assay. Gram-negative bacteria were not inhibited. Bacteriocin production was observed at 10 h, and was maximized at 16 h in MRS broth incubated at $37^{\circ}C$. In a beaker sausage fermented with P. acidilactici KFRI 168, viable counts of Stph. aureus, Salmonella, Escherichia coli, Clostridium perfringens, and Lis. monocytogenes were reduced by 2.8, 2.3, 2.4, 0.7, and 0.5 log CFU/g, respectively. Inoculated P. acidilactici KFRI 168 maintained its viable count of more than $10^8$ CFU/g during the whole fermentation period, and it took less than 8 h to reduce sausage pH below 5.

• Korean Journal of Food Science and Technology
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• v.36 no.1
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• pp.116-122
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• 2004

Growth of Lactobacillus acidophilus in flour was investigated for production of noodle and bread. L. acidophilus grew when fermented in flour, and growth continued upon fermentation with salt for 72 hr. pH of L. acidophilus-fermented flour with salt decreased up to 72 hr, reaching 3.06. Fermented flour with salt showed no decomposition as compared to that without salt. In flour fermented by L. acidophilus, amounts of lactic and acetic acids produced increased with incubation time, and reached, after 72 hr incubation, 6,821 and 0.191 mg/g, respectively, resulting in significantly higher production of lactic acid. Viscosity of fermented flour with salt increased, whereas that without salt decreased with incubation time. Results reveal L. acidophilus-fermented flour with salt could be applied as effective agent in noodle and bread productions.

• Preventive Nutrition and Food Science
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• v.9 no.1
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• pp.7-13
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• 2004

Lactic acid fermentation of prickly pear extract (PPE) was performed by Lactobacillus rhamnosus LS, Lactobacillus bulgaricus, and Lactobacillus brevis. The PPE was pasteurized to eliminate indigenous microorganisms as well as to dissolve the partially insoluble pulp. The PPE fermented without yeast extract by L. rhamnosus LS exhibited 0.57％ acidity and 3.5${\times}$10$^{8}$ CFU/mL bacteria count. With the addition of 0.2% edible yeast extract the PPE fermented by L. rhamnosus LS exhibited 1.15％ acidity,2.7${\times}$10$^{9}$ CFU/mL bacteria count and 95.0% retention of red color. When 5％ fructose syrup was added, the PPE fermented by L. rhamnosus LS had 1.09% acidity, 6.5${\times}$10$^{8}$ CFU/mL, and 97.7% retention of red color. With 1∼3% (w/v) concentrations of starter, the PPE fermented by L. bulgaricus and L. brevis showed 0.97% and 0.65% acidities, respectively. The viable cell counts from L. rhamnosus LS fermentation were higher compared with those of other LAB. During cold storage at 4$^{\circ}C$, the viable cell count was well maintained for 3 weeks, but then rapidly decreased. The red pigment was highly stable during cold storage for 4 weeks. The pasteurized PPE fortified with 5% fructose syrup, 0.2% yeast extract, and 0.05% CaCO$_3$ was successfully fermented by inoculating with 3% LAB and incubating at 3$0^{\circ}C$ for 2 days. Both viable cell counts and the red color of the fermented PPE were well maintained during cold storage for 3 weeks.

• Preventive Nutrition and Food Science
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• v.8 no.1
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• pp.54-60
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• 2003

To develop a functional chungkookjang; the anticancer effects of chungkookjangs prepared with different varieties of soybeans, starters, fermentation periods and seasoning additive ratios; were studied against AGS human gastric adenocarcinoma cells using the MTT assay, at different stages chungkookjang processing. The chungkookjang samples exerted different antiproliferative effects according to the variety of soybeans used. The chungkookjangs manufactured with soybean var. manrikong exhibited the highest cytotoxicity against AGS human cancer cells. The chungkookjangs fermented with rice straw and B. licheniformis strongly inhibited the growth of the AGS human cancer cells. All fermented chungkookjangs had a strong inhibitory effect on the growth of the cancer cells; however, the non-fermented soybean (chungkookjang) showed a low inhibition rate. The fermented chungkookjangs mixed with red pepper powder (RPP) and garlic exhibited strong antiproliferative effect against the cancer cells, and chungkookjang prepaved with 1.1 % RPP and 1.1 % garlic showed the highest cytotoxicity against the cancer cells. The functional chungkookjang fermented with soybean variety of manrikong and B. licheniformis for 3 days at 4$0^{\circ}C$ and then mixed with 7.9% salt, 1.l% RPP and 1.1% garlic, exhibited a higher antiproliferative effect than the chungkookjangs prepared by traditional or modified methods, according to the MTT assay. The functional chungkookjang exhibited a similar anticancer effect to the traditional doenjang. These results indicate that the fermentation period and the ratio of seasoning additives, as well as the variety of soybeans and starter cultures may affect the degree of the anticancer effect of chungkookjang.

• Food Science and Preservation
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• v.22 no.3
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• pp.353-360
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• 2015

Yakju, a Korean traditional alcoholic beverage, is made from rice and Nuruk. In this study, the fermentation characteristics of Yakju was investigated using rice and rice starch. Ingredients was classified into raw material (rice, rice starch) and starter (enzyme supplements, modified Nuruk, traditional Nuruk, and yellow rice koji) for fermentation. The crude protein content of rice, rice starch, and starter were determined as follows (%): rice 6.69, rice starch 0.44, enzyme supplements 7.84, modified Nuruk 15.29, traditional Nuruk 14.28, and yellow rice koji 7.28. The alcohol content of rice with traditional Nuruk ($20.13{\pm}0.12%$) was higher than other Yakju. The concentration of organic acids of rice starch-based Yakju (389.83~538.34 mg%) was higher than that of rice Yakju (259.27~357.70 mg%). The concentration of nitrogen compound of rice Yakju (498.38~5976.93 ppm) was higher than that of rice starch-based Yakju (600.43~4463.79 ppm). In line with these findings, further studies will be necessary for the quality analysis of the rice, rice starch and fermented starter (enzyme supplements, modified Nuruk, traditional Nuruk and yellow rice koji).

• Journal of the East Asian Society of Dietary Life
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• v.21 no.5
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• pp.661-668
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• 2011

This study was conducted in order to determine the optimum conditions for the production of fermented grapefruit extract showing high cell growth, antioxidant activity and total flavonoid content. Five lactic acid bacterial strains - Lactobacillus plantarum KCTC3104, Lactobacillus brevis KCTC3102, Weisella cibaria KCTC3746, Leuconostoc citreum KCTC3526 and Leuconostoc mesenteroides KCTC3505 - were evaluated first in order to determine the optimum strain able to grow with high efficiency on grapefruit as a substrate and possesses higher antioxidant activity and flavonoids content. Among these strains, L. mesenteroides KCTC3505 was selected as a starter culture. To estimate the available or effective content of grapefruit in basal medium, the effects of 30%, 50%, and 70% grapefruit contents on the performance of fermentation were tested, and it was found that grapefruit can be added at 70% levels to medium. In this study, three factors of fermentation conditions - incubation time, sucrose, and glucose contents - were evaluated for their effects on fermentation performance. Taguchi experiment design was employed and the responses of experiments were calculated using signal and noise ratio calculation with larger-the-best characteristics. Finally, the optimum conditions for the manufacture of fermented grapefruit extract were as follows: grapefruit 70%, sucrose 10 g/L, glucose 10 g/L, sodium acetate 1 g/L, NaCl 1 g/L, dipotassium phosphate 0.1 g/L, magnesium sulfate 0.01 g/L and 16 hr of incubation.