• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.2
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• pp.148-157
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• 2005

This study was investigated to determine antimicrobial activity of the water and ethanol extracts of Korean wild green tea, semi-fermented tea, and fermented tea. Antimicrobial activity was examined against 8 kinds of several microorganisms. The minimum inhibitory concentration (MIC) of the water and ethanol extracts of green tea showed the most active antimicrobial activity against B. subtilis 0.2 mg/mL in Gram positive bacteria and P. fluorescens 0.3∼0.5 mg/mL in Gram negative bacteria. But the extracts did not show antimicrobial activity against lactic acid bacteria and yeast at the level of less than 1 mg/mL. Antimicrobial activity got lower as tea got more fermented. Antimicrobial activity of ethanol extracts from green tea, semifermented tea, and fermented tea was stronger than that of water extracts. Antimicrobial activity of the water and ethanol extracts of green tea, semi-fermented tea, and fermented tea was not destroyed at 50∼121$^{\circ}C$, and pH 3∼11, which proved to be very stable when given over heat, acid & alkali treatment. The ethanol extract of green tea, semi-fermented tea, and fermented tea was fractionated in the order of hexane, diethyl ether, ethyl acetate and water fraction. The highest antimicrobial activity was found in the water fraction, but not found in hexane fraction, while antimicrobial activity of fermented tea was not found in ether fraction.

• Food Science and Preservation
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• v.15 no.6
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• pp.909-914
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• 2008

This study investigated microbial populations and the sensory quality of sikhae including globefish (GLS), flounder (FLS), gastropods (GAS) and whelks (WHS) during storage at 4C for 16 d following fermentation at 10C for 4 d. General bacterial numbers increased to 102 in GLS and FLS, and to 1045 in WHS and GAS after the 20 d fermentation/storage period. Lactic acid bacteria increased to 108 log cycle in GLS and FLS after 10 d ripening time, and reached this level in GAS and WHS after 15 d and 20 d, respectively. After 20 days the number of lactic acid bacteria in each of the four samples was 108. There were 104105 yeast cells/g in each of the four samples after 20 d. The number of Leuconostoc increased to over 108 log cycle after 10 d in GLS and FLS, and 15 days in GAS for WHS the increase was to 107 log cycle. The pH values of GLS, FLS, GAS and WHS 4.42, 4.56, 4.31 and pH 4.26, respectively. The Sikhae acidity for all four samples ranged from 1.551.85%. From the sensory evaluation the overall acceptability was in the order of FLS > GLS > GAS > WHS.

• Korean journal of food and cookery science
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• v.28 no.2
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• pp.207-214
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• 2012

In this study, cabbage ($Brassica$ $oleracea$ var. $capitata$) Kimchi was made packed into four kinds of packaging materials, PET vessel, PP tray, OPP/AL/PE film and Nylon/PE/LLDP film, and the effects of these packaging materials on Kimchi quality characteristics, such as lactic acid bacteria counts, salinity, sugar contents, pH, total acidity, electron donating ability were examine as well as their effects on the sensory qualities after storage at a temperature of $4^{\circ}C$. The pH change ranged from pH 6.24 to 6.43 shortly after manufacture, and did not significantly change until 7 days of storage. However, it began to decrease rapidly after 14 days. On the 35th day of storage, the acidity was 0.79% in the PET vessel and 0.83% in OPP/AL/PE. Therefore, the PET vessel and OPP/AL/PE were considered appropriate packaging materials for Kimchi storage. The salinity did not change significantly during the storage period, and the sugar content generally increased in the four kinds of packaging materials, but decreasing after the 7th day of storage. After 14 days of storage, the Kimchi stored in the OPP/AL/PE film showed the highest lactic acid bacteria counts. Although the electron donating ability was the highest after proper time for fermentation, it decreased in all the packaging materials after the proper time for fermentation. However, the OPP/AL/PE film had an antioxidant potential of up to 93.18%. In the sensory evaluation, fermented Kimchi was found to be superior unfermented Kimchi. In addition, the Kimchi stored in the OPP/AL/PE film for 14 days showed the high score of 6.70 and 6.60 in overall preference. Therefore, the results of this study provide basic knowledge on the fermentation level and packaging material's condition for commercialization of small packed cabbage Kimchi. Henceforth, industrialization must include a variety of studies under these conditions to increase the merchantability.

• Korean Journal of Food Science and Technology
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• v.38 no.4
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• pp.475-482
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• 2006

The quality characteristics and functional properties of fermented soybean by lactic acid bacteria (FSB) were investigated and compared with those of soybean (control) and commercial cheonggukjang Powder (CGP). The crude protein, lipid, and fiber contents of FSB were similar to those in CGP. The vitamin $B_2$ content in FSB (1.4 mg%) was similar to the control (1.3 mg%) whereas it was remarkably low in the CGP (0.2 mg%). The bright yellow color of FSB determined by Hunter's colormeter was quite different from the dark reddish brown color of the CGP. The pH of FSB was the lowest and thee amino-nitrogen was 517.2 mg%, which was higher than that in CGP (468.1 mg%). Glutamic acid, aspartic acid and leucine were the most abundant amino acids. In particular, the increase in the glutamic acid level was noticeable in FSB. The fatty acid compositions of FSB and CGP were similar to the control. However, the sucrose and fructose levels were lower after fermentation but the glucose level was higher. The results of isoflavone analysis by HPLC showed that the levels of daidzein and genistein in FSB were as much as 48.33 and 52.82 mg%, respectively, which is higher than that found in CGP. The DPPH free radical scavenging effects of FSB and CGP were 1.8 times higher an those of the control. The fibrinolytic activity determined by the diameter of the lysed area on the fibrin plate was the most effective in FSB. In conclusion, it is believed that FSB has a similar or higher quality than CGP. Therefore, FSB is expected to be good functional food material.

• Korean Journal of Food Science and Technology
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• v.31 no.3
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• pp.794-801
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• 1999

This study was conducted to investigate sorbitol utilization of Lactobacillus species isolated from Kimchi and the effects of sugar, starch syrup and sorbitol on the pH, titratable acidity, microorganism and sensory evaluation of baechu Kimchi during fermentation at $10^{\circ}C$. Three species among ten Lactobacillus species isolated from Kimchi could not utilized medium with sorbitol. The pH of baechu Kimchi with addition of 1% sugar sources and sorbitol were similar to pH of control baechu Kimchi, while the titratable acidity were different between samples. The titratable acidity of baechu Kimchi with addition of sugar sources was higher than control. Increasing in sorbitol addition, the titratable acidity of haechu Kimchi was more remarkable lower than control during fermentation proceeded. The total number of viable cells and Lactic acid bacteria were not significantly difference among those of Kimchi samples. In the chewiness of textural properties, baechu Kimchi with addition sorbitol showed higher score than control. However, Kimchi samples prepared with 1% sugar sources were not significantly differences in sensory properties, while the Kimchi samples with 5, 10% sorbitol were higher score than control in the overall acceptability and texture.

• Food Science and Preservation
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• v.14 no.5
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• pp.526-530
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• 2007

The effects of kwamaegi (0, 6, 12 and 18%, all w/w) on the quality characteristics of Kimchi during fermentation at $10^{\circ}C$ were investigated. The mixtures are denoted KK. The late of decrease in pH during KK fermentation was lower than that of control. The number of total microbes (T) in Kimchi controls fermented for 14 days did not differ, and were in the range of $8.64{\sim}8.68\;log\;CFU/g$, whereas the numbers of lactic acid bacteria (L) in KK were higher than in controls. The L/T(%) was 78.41 in control, 85.76 in 6% KK and $93.68{\sim}94.25%$ in the 16% or 18% KK samples. The hardness of tissue ($2.98{\sim}3.66{\times}10^7\;dyne/cm^2$) in KK fermented for 14 days was higher than that of control ($2.67{\times}10^7\;dyne/cm^2$). The content of alcohol-insoluble substances in KK juice (1.281.08 g/100 g) was lower than that of control (1.45 g/100 g). In sensory evaluation, the appearance and texture of KK were better than those of control. Although some fishy flavor was noted in KK, this did not affect acceptability. Sourness was less, whereas ripened taste and overall acceptability were higher in KK (especially 12% KK) compared to control.

• Food Science and Preservation
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• v.20 no.2
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• pp.199-206
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• 2013

To evaluate peanut sprouts as a functional food material, the quality characteristics and antioxidant activities of soybean yoghurt with different percentages (0.5, 1.0, 2.0, and 3.0%) of peanut sprout powder (PSP) contents were investigated. The pH of soybean yogurt with PSP decreased in a time- and dose-dependent manner during fermentation, whereas the titratable acidity increased under the same conditions. The Hunter L value (lightness) decreased while the b value (yellowness) and a value (redness) increased as the PSP concentration in soybean yogurt increased. Prior to fermentation, the sugar content of the soybean yogurt increased as the PSP level increased, but the contents decreased as fermentation progressed. Meanwhile, the viscosity of the soybean yogurt increased during fermentation, and the lactic acid bacteria population was higher than that of the control. The sensory properties, including the flavor, color, taste, and overall acceptability, of the soybean yogurt containing 0.5 and 1% PSP, respectively, were higher than those of other tested yoghurts (with 0, 2.0, and 3.0% PSP contents). The antioxidant activity of the soybean yogurt significantly increased at the PSP concentrations of over 1.0%. These results suggest that the addition of PSP has beneficial effects on the quality and functionality of soybean yogurt, and that the addition of 1.0% PSP is the most suitable for manufacturing soybean yogurt.

• Korean Journal of Food Science and Technology
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• v.32 no.5
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• pp.1142-1148
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• 2000

This study was conducted to investigate the effect of different salting conditions, short-time salting(SS) and long-time salting(LS), on the fermentation and quality of dandelion kimchi. The desirable salt concentration of brine and salting time evaluated by salting degree were 16 hrs at 5% brine, 8 hrs at 10% brine and 4 hrs at 15% brine, respectively. Among them, the best quality of salted dandelion was salting of 10% brine for 8 hrs. But the bitter taste in salted dandelion treated by SS was remained. The proper condition to salt and remove the bitter taste in salted dandelion together was salting by LS, which was salted for 4 days in 100% brine changed once a day. pH of the dandelion kimchi salted for 8 hrs in 10% brine during fermentation at $10{\times}$ was lower than that of LS kimchi, but acidity, total microbe, number of lactic acid bacteria, content of reducing sugar and vitamin C were higher than those of LS kimchi. The optimum- fermentation periods of SS(salted for 8 hrs in 10% brine) and LS kimchi evaluated by sensory test were 40th and 50th day, respectively.

• Journal of The Korean Society of Grassland and Forage Science
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• v.24 no.1
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• pp.61-70
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• 2004

Silage additives are needed to increase the quality of whole crop rice silage which seldom produce without the additives due to both high pH and butyric acid concentrations. Little information, however, is available about the silage fermentation of whole crop rice added with silage additives in Korea. This study was conducted to determine the optimum levels of silage additives by evaluating the effects of latic acid bacteria (LAB) and formic acid concentrations on the silage quality of whole crop rice harvested at different mature stages. Field study was established early in May until October 7th on a rice field at Yupori, Sinbuk-yeup, Chunchon, Kangwon-Do. "Ilpum" mutant rice was harvested at six different mature stages; booting stage (17 Aug.), milk-ripe stage (27 Aug.), dough stage (7 Sep.), yellow ripe stage (17 Sep.), dead ripe stage (27 Sep.) and full ripe stage (7 Oct.). Each sample was ensiled in three different ways; with 1) LAB (0.05, 0.1 and 0.2% of sample wt), 2) formic acids (0.2, 0.3 and 0.4% of sample wt.) and 3) no additive. The additive levels did not affect dry matter content, crude protein, fiber and total digestable neutriant concentrations at all stages. Addition of additives significantly decreased the silage pH and butyric acid concentrations which tended to be more decreased with higher levels of additives. Latic acid concentrations were higher with the use of additives, especially with LAB. The lower concentrations of ammonia-N were observed in additive treatments at all stages, but the concentrations of ammonia-N did not differ according to the additve levels after yellow ripe stage (0.69, 0.60 and 0.71% of DM in 0.05, 01 and 0.2% of LAB, respectively; 0.64 0.59 and 0.75% of DM in 0.2, 0.3 and 0.4% of formic acid, respectively). These results indicate that the optimum addition levels of LAB and formic acid are 0.5∼0.1% and 0.2∼0.3%, respectively, on which the high quality of rice whole crop silage was produced. produced.

• Journal of Applied Biological Chemistry
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• v.65 no.4
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• pp.287-298
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• 2022

This study investigated the changes in the physiochemical property, phytochemical content, nutritional content and antioxidant activity of Polygoni multiflori Radix by steam, aging, and fermentation. After processing Polygoni multiflori Radix (PMR), pH slightly decreased, while acidity increased (pH 5.70→4.78, acidity 0.23→0.29%). The reducing sugar content increased after aging and fermentation from 1.19 mg/g (PMR) to 1.40 (fermented PMR, FPMR), 1.30 (red PMR, RPMR), 1.53 (fermented red PMR, FRPMR), 1.99 (black PMR, BPMR), and 2.33 mg/g (fermented black PMR, FBPMR). Total phenolic content was highest in PMR (6.05 mg/g) and total flavonoids and maillard product were increased after aging and fermentation of PMR, and were the highest in BPMR (1.60 mg/g) and FBPMR (2.76 O.D.), respectively. The major phytochemical was 2,3,5,4'-tetrahydroxystilbene-2-0-α-glucoside, which were highest in PMR (64.9 mg/g) with 46.47 mg/g at FPMR, 33.94 mg/g at RPMR, 48.76 mg/g at FRPMR, 36.68 mg/g at BPMR and 34.35 mg/g at FBPMR. The main fatty acids and free amino acids were detected as palmitic acid (C16:0) and proline, respectively. Generally, 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt radical scavenging activities and FRAP reducing powers were shown high in PMR (39.06%, 98.32%, and 2.61 O.D. in extracts concentration 1.0 mg/mL), then were decreased after aging and fermentation.