• Korean Journal of Food Science and Technology
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• v.39 no.1
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• pp.61-65
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• 2007

In order to extend the viability of aerotolerant Bifidobacterium animalis DY-64, fructooligosaccharide was added to kimchi containing the bifidobacteria. Baechu-kimchi made with Chinese cabbage was prepared with B. animalis DY-64 and fructooligosaccharide. Physicochemical and microbial changes of the kimchi were evaluated during fermentation at $4^{\circ}C$. Bifidobacteria survived longer in kimchi containing fructooligosaccharide than in kimchi not containing the oligosaccharide. The viable cell counts of Lactobacillus spp. and Leuconostoc spp. and the organic acid content of fructooligosaccharide-added kimchi were higher than those of bifidobacteria or conventional kimchi. The sour taste and sourness of fructooligosaccharide-added kimchi were as high as that of conventional kimchi. These results show that the addition of prebiotic fructooligosaccharide in kimchi enhanced the viability of bifidobacteria during functional kimchi fermentation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.4
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• pp.417-425
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• 2015

Semi-dried conger eel Conger myriaster is considered as a health food in Korea due to its richness in vitamins, minerals, proteins and omega-3 fatty acids. This study characterize the sanitary quality of commercial semi-dried conger eel for developing high quality semi-dried products and suggested the guideline for controlling the quality. Moisture content ranged from 41.2% to 73.4% (mean: 61.5%), volatile basic nitrogen ranged from 16.1 to 93.6 mg/100 g (mean: 55.1 mg/100 g), and peroxide value ranged from 15.2 to 69.8 meq/kg. Viable cell counts ranged between 6.51 and 8.53 log CFU/g, while the Escherichia coli count ranged from undetectable to 4.6 log CFU/g. Based on these chemical and microbial findings, we suggest that provisions be established for development of high quality semi-dried conger eel as follows: 50-68% for moisture content, < 50 mg/100 g for volatile basic nitrogen content, < 60 meq/kg for peroxide value, and negative for E. coli. Among the 16 commercial semi-dried conger eel products used in this study, the standard-passed product was only GS-L.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.5
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• pp.467-472
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• 2017

There is increasing interest in developing flavor-enriched concentrate using byproducts of skipjack tuna Ktsuwonus pelamis as a replacement for commercial beef bone extract concentrate (CBB-EC). This study was compared on sanitary and nutritional characteristics between skipjack tuna frame extract concentrate (ST-EC) and CBB-EC as a control of skipjack tuna frame extract concentrate. The moisture contents of CBB-EC and ST-EC 41.4-4.9% and 45.3%, respectively. The results of viable cell counts and E. coli assays suggested that CBB-EC and ST-EC is a safe and sanitary for use in food. There were no differences in peroxide values among CBB-ECs. The total amino acid contents in CBB-EC and ST-EC were 25.6-29.3 g/100 g and 37.9 g/100 g, respectively, and the major amino acids present glutamic acid, proline, glycine, alanine and arginine. Regardless of kinds of the mineral, mineral contents of ST-EC higher than those of CBB-EC. The major fatty acids were 16:0, 18:0 and 18:1n-9 in CBB-EC, 16:0, 18:1n-9 and 22:6n-3 in ST-EC. These results can be used as background information to develop flavor-enriched concentrates from byproducts of skipjack tuna as replacement for CBB-EC.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.9
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• pp.5693-5699
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• 2014

The influence of the flour types, including bread flour and cake flour on sourdough preparation was investigated. As starters, mixed probiotic microorganisms, including Bifidobacterium longum KCTC 5734, Enterococcus faecium KCTC 13410, and Lactobacillus acidophilus KCTC 3925, or Saccharomyces cerevisiae fermented separately for 15h at $30^{\circ}C$, were combined and then fermented for 10h at $30^{\circ}C$. The combined process with cake flour showed a 100-fold and two-fold increase in [$H^+$] and titratable acidity, respectively. This was also reflected in the viable cell counts and lactate concentration in sourdough. These results show that bread flour and cake flour may be useful for the production of sourdough.

• Applied Biological Chemistry
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• v.44 no.2
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• pp.81-87
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• 2001

Oyster jeot-gal were prepared in the form of salt-fermented oyster and oyster in soy sauce tentatively and used for investigation the retarding effect of its fermentation in a vacuum from the physicochemical and microbiological points of view. $_PH$ value decreased slightly but amino-N (AN) and volatile basic nitrogen (VBN) increased inversely during the fermentation periods. AN contents were greater in vacuum fermentation than in non-vacuum, whereas VBN were greater in non-vacuum. Total viable cell counts were similar to trend of gentle decrement after increment to some degree but showed higher in non vacuum than in vacuum. In vacuum product, total amino acid contents increased with the elapse of fermentation days or in time of reduction those were higher than in non-vacuum. On the results of chemical analysis, it showed that fermentation was delayed in vacuum and that vacuum fermentation was effective for the shelf-life extension of jeot-gal.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.2
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• pp.121-126
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• 1994

The present study was designed to investigate effects of the addition of potato homogenates on fermentation control of salted anchovy. With the addition of $8\%$ (w/w) potato homogenates(P), amino-N content and pH were maintained at lower values in the muscle and juice of salted anchovy during all fermentation periods, And high values in external appearance of the salted and fermented anchovy-body during fermentation period were recorded. Consequently, the suppressing effect on the fermentation of salted anchovy of the addition of $8\%$ (w/w) potato homogenates was proved. As for the factors related to the suppressive effects on fermentation, there was no change in amino-N content, and viable cell counts and pH values were maintained.

• Journal of Microbiology and Biotechnology
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• v.12 no.1
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• pp.8-13
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• 2002

The isoflavone glycosides are hydrolyzed by ${\beta}$-glucosidase from gut microbes to the bioactive aglycones. However, the specific bacteria from the human intestinal tract that are involved in the metabolism of these compounds are not known. This study was undertaken to develop a fermented soymilk which converts isoflavones to the more bioactive aglycones form using a Bifidobacterium strain. The ${\beta}$-glucosidase activity of 15 Bifidobacterium strains were measured during cell growth. Among them, Bifidobacterium sp. Int-57 was selected for this study, because it has the highest ${\beta}$-glucosidase activity. Growth, acid development, ${\beta}$-glucosidase activity, and the hydrolysis of daidzin and genistin were investigated in four soymilks inoculated with Bifidobacterium sp. Int-57. After 12 h of fermentation, the counts of viable Bifidobacterium sp. Int-57 in all the soymilks reached a level of more than $10^8$ cfu/ml, which was then maintained. The pH of soymilks started to decrease rapidly after 6 h of fermentation and leveled off after 18 h. The titratable acidity of BL# 1 soymilk, BL#2 soymilk, and JP#l soymilk increased from 0.18 to 1.21, 1.15, and $1.08\%$ over the fermentation period, respectively. After 24 h of fermentation, the $\beta$-glucosidase activity in BL#1 soymilk, BL#2 soymilk, JP#l soymilk, and JP#2 soymilk increased to 59.528, 40.643, 70.844, and 56.962 mU/ml, respectively. The isoflavone glycosides, daidzin and genistin, in soymilks were hydrolyzed completely in the relatively short fermentation time of 18 h. These results show that Bifidobacterium sp. Int-57 can be used as a potential starter culture for developing fermented soymilk which has completely hydrolyzed isoflavone glycosides.

• Journal of Life Science
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• v.12 no.5
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• pp.535-543
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• 2002

To investigate the possibility of processing semi-dried jellyfish and to examine its keeping quality, the factors such as moisture content, pH, volatile basic nitrogen (VBN), viable cell counts, color value and texture were analyzed. For processing of the semi-dried product, optimum conditions of drying temperature and drying time were $25^{\circ}C$ and 90min, respectively, under 60 $\pm$ 5% of relative humidity and 2 m/sec of air blast speed. The shelf-life of the products, vacuum-packing method in nylon/polyethylene/linear low density polyethylene (0.015/0.045/0.040 mm) laminated film bag was at least 6 weeks during storage at 4$^{\circ}C$, while that of air packaged one was at least 4 weeks. In case of 2$0^{\circ}C$ storage the shelf-life of the products was at least 3 weeks in both air and vacuum packaged ones.

• The Korean Journal of Food And Nutrition
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• v.13 no.1
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• pp.36-44
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• 2000

Survival of pathogenic bacteris(S. aureus, L. monocytogenes, E. coli and S. typhimurium) in tryptic soy broth containing green tea water extract(GTW), green tea ethanol extract(GTE), potassium sorbate (PS) and sodium benzoate(SB) stored at various pH was evaluated. Tryptic soy broth(TSB) containing 0∼2%(w/v) of green tea extracts and preservatives adjusted to pH 5.5, 6.0, 6.5 and 7.0 was inoculated approximately 105 CFU/ml of pathogenic bacteria and incubated at 35$^{\circ}C$ for 24∼48 hours. Survival of bacteria was determined by viable cell counts of bacterial culture at each pH. Minimum inhibitory concentration(MIC) and minimum bactericidal concentration(MBC) of green tea extracts and preservatives against pathogenic bacteria were derived from survival curves of each bacteria. Antibacterial activities of green tea extracts increased with increasing pH but those of preservatives decreased with increrasing pH. S. aureus was the most sensitive strain to GTW and GTE but the most resistant to PS and SB. The MICs of green tea extracts to S. aureus were 0.52∼0.98% at pH 5.5∼6.0 and non inhibitory at pH 7.0. S. typhimurium was the most resistant to green tea extracts while the most sensitive to SB. The MICs of green tea extracts to S. typhimurium were 0.46∼1.62% at pH 5.5∼6.0 and 2% of PS was bactericidal at pH 5.5. 1.0∼2.0% of GTE were bactericidal to all strains tested except L. m9oncytogenes at pH 7.0. GTE was most efficient at inactivating pathogenic bacteria, generally followed by GTW, PS and SB.

• Korean journal of food and cookery science
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• v.29 no.3
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• pp.267-274
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• 2013

Demand for a rice cake, a popular traditional food in Korea, is rising, but its industrial-scale production is extremely difficult due to its short shelf-life caused by starch retrogradation and microbial spoilage. By means of the sourdough fermentation technique, we attempt to develop rice cakes with a longer shelf-life. Heterofermentative lactic acid bacteria (Weissella koreensis HO20, Weissella kimchii HO22) isolated from kimchi were used to ferment wet-milled rice flour for their abilities to produce exopolysaccharides and to inhibit the microbial spoilage of rice cakes. After 24 hr of fermentation at $25^{\circ}C$, viable cell counts in rice dough increased from $10^6$ CFU/g to $10^8$ CFU/g and total titratable acidity increased from 0.05% to 0.20%, whereas pH decreased from 6.5 to 5.1. Fermented rice flour showed significantly lower peak, trough, and final viscosities as well as breakdown and setback viscosities measured by rapid viscoanalyzer. Both lactic acid bacteria showed in vitro antifungal activity against Penicillium crustosum isolated from rice cakes. The antifungal activity remained constant after the treatments with heat, proteinase K and trypsin, but fell significantly by increase of pH. Rice cakes made of fermented rice flour were found to retard mycelial growth of P. crustosum. The degree of retrogradation as measured by the hardness of the rice cake was significantly reduced by the use of fermented rice flour. The results suggest that use of fermented rice flour has a beneficial role in retarding starch retrogradation and in preventing fungal growth, hence extending the shelf-life of rice cakes.