• Korean Journal of Microbiology
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• v.51 no.3
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• pp.300-307
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• 2015

For selecting Bacillus strains producing high-quality Cheonggukjang, 8 strains were isolated from the different Cheonggukjang samples. Seven of them exhibited the highest 16S rRNA gene sequence similarity value of over 99.9% to Bacillus subtilis subsp. subtilis and one of them showed the similarity to B. licheniformis. All the strains showed positive activities for amylase, cellulase, protease and lipase, and 6 strains are positive for fibrinolytic activity. To confirm the safety of the strains isolated from the samples of Cheonggukjang which are manufactured by traditional method, strains were analyzed for the presence of seven toxin genes of Bacillus cereus and results were found negative. And 7 strains did not produce at all or merely produce both histamine and tyramine, the representative biogenic amines. Biogenic amine degradation analysis by HPLC revealed that, most of them exhibited tyramine degradation activity. For Cheonggukjang fermented by artificial inoculation of selected strains, fermentation property, sensory test, volatile basic nitrogen production and metabolic profiles by $^1H-NMR$ were tested. Seven strains were confirmed to make high-quality Cheonggukjang.

• Korean Journal of Microbiology
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• v.48 no.2
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• pp.147-155
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• 2012

To improve of the quality of Korea traditional wheat-rice wine (makgeolli) production, we used a rice fermentation starter (rice nuruk) made by inoculation of Rhizopus oryzae CCS01 which was isolated and selected from commercial nuruk. Amylase activity of a rice nuruk was 1.8-2.4 times higher than those of commercial nuruks. The best acceptability of wheat-rice wine in a sensory test was observed at 4 : 6 ratio of wheat-rice mash at experimental condition. During the fermentation period, pH of wheat-rice makgeolli made with a rice nuruk was higher compared to those made with commercial nuruks such as Sanseong, Jinju, and Songhak. Acidity of makgeolli mash was lower in case of using a rice nuruk and birx and alcohol production were higher compared to those of makgeolli mash using commercial nuruks. Highest alcohol production was observed at makgeolli mash using a rice nuruk and 12% of alcohol was produced at fermentation end. These results suggest that production of a new type of wheat-rice makgeolli using a rice nuruk was possible.

• Journal of Animal Science and Technology
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• v.48 no.2
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• pp.269-278
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• 2006

This study was performed to extend the shelf-life of duck breast treated with NaCIO(20, 50ppm), lactic acid(1, 2%) and acetic acid(1, 2%). Changes in microbial counts, storage characteristics and color values of duck breasts were determined during storage at 4℃ for 7 days. Although pH values were not different on the first day of storage. they increased up to 3rd days of storage and decreased gradually thereafter. Thiobarbituric acid reactive substances(TBARS) of duck breasts treated with lactic acid and acetic acids were lower TBARS than those with lactic acid on the 7th days of storage. Volatile basic nitrogen(VBN) didn't differ among the treatments(P>0.05). Although the microbial counts were increased in all treatments, acetic acid treatment had lower microbial counts among the treatments during storage. These results indicated that acetic acid would be the best treatment to extend the shelf-life of duck breasts among others.

• Korean Journal of Microbiology
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• v.42 no.2
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• pp.95-102
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• 2006

To evaluate bacteriological water quality of groundwater in Yeungnam Province, samples were taken from 123 locations during summer and 117 locations during winter. The medians of heterotrophic plate counts.(HPCs) were 30 CFU/mL for the summer samples and 40 CFU/ml for the winter, and more than 25% showed HPCs higher than 100 CFU/ml. Coliform bacteria were detected from 46% of the summer samples and 30% of the winter. In these coliform-positive samples, the medians of coliform counts were 20 CFU/ml for the summer samples and 4 CFU/ml for the winter. Genera such as Citrobacter, Enterobacter, Escherichia, Klebsielia, Pantoea, Rahnellia, and Serratia were identified from the coliform isolates; among them, 48% were members of the genus Enterobacter. While E. cloacae, E. amnigenus, and K. pneumoniae were the most frequently isolated species, E. coli was isolated only from 1 location. The coliform counts were positively correlated with the HPCs, which also positively correlated with water temperature. The results of present study provide further insight on the extent of groundwater contamination with coliform bacteria.

• Journal of the Korean Applied Science and Technology
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• v.34 no.4
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• pp.1066-1075
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• 2017

This study was carried out to determine the functional works and basic ingredients of Sagoonja-Tang on sponge cake. The experimental groups consisted of 6% mixtures of five (Ed-confirm the number) kinds powders : S1 for Sagoonja-Tang powder, S2 for Panax ginseng, S3 for Poria cocos, Koidz, S4 for Atractylodes macrocephala, and S5 for Glycyrrhiza uralensis Fisch. The volume of sponge cake somewhat decreased after adding the ingredients, and the volume differences in order from highest to lowest, were control>S1>S3>S2>S4>S5. In the microbiological quality test, viable cell counts were high in control groups of sponge cake, and the numbers of viable cell for control sponge cake reached to $9{\times}10^7CFU/g$ on the 7th day of storage, and decreased to $2.5{\times}10^5CFU/g$ on the 10th day of storage. All sponge cakes added with ingredient's powder showed pretty low viable cell counts. Especially, the group S5 showed the lowest counts of $1.2{\times}10^2CFU/g$ on the 7th day of storing. In the texture analyses of sponge cake, All groups showed higher degree of hardness, gumminess and chewiness than SC. The antioxidative activity of the Sagoonja-Tang's ingredients was measured. The POV value measured was S5>S4>S3>S2 >S1>control in order of highest to lowest. In sensory test, the overall acceptability of sponge cake was from highest to lowest S3>SC S2>S1>S5>S4.

• Korean journal of food and cookery science
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• v.31 no.4
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• pp.387-394
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• 2015

The red snow crab lives at a depth 200-2,000 m in the east coast. It has a smooth taste with a rich texture. However mostly red snow crab are only utilized materials. For seafood development, research is needed on using red snow crab in various products. In this study, quality changes in fried rice prepared with red snow crab meat, red snow crab emulsion sauce and red snow crab effluent were investigated. Physicochemical, microbiological and sensory characteristics were determined during storage at -20, 4 and $25^{\circ}C$ for 5 weeks to assess changes in the quality of the fried rice. The pH and acidity values did not show any significant differences at $-20^{\circ}C$. The VBN and TBA values of fried rice stored at 4 and $25^{\circ}C$ were significantly higher than those of fried rice stored at $-20^{\circ}C$ during the same storage period. The viable cell count of the fried rice stored at $-20^{\circ}C$ changed little during the storage period. During storage at $25^{\circ}C$, the overall quality was initially 8.0, but rapidly decreased to 1.0 after 5 weeks. In conclusion, the best storage temperature for both quality and safety was $-20^{\circ}C$. The storage condition for instant rice containing red snow crab affects the quality and we confirmed the applicability of using materials from red snow crab.

• Korean Journal of Food Science and Technology
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• v.21 no.2
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• pp.283-288
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• 1989

The effect of storage temperature on the quality characteristics of meat sausage was investigated. Thus, the quality characteristic changes of meat sausage were discussed through physico-chemical and microbiological analysis. The results were summarized as follows; Volatile basic nitrogen(VBN) was increased more rapidly at $40^{\circ}C$ than at $10^{\circ}C$, $20^{\circ}C$ and fluctuating temperature $(10/40^{\circ}C)$. In physico-chemical analysis of meat sausage, the values of VBN , viable cell counts were increased with increase of temperature during storage, while thiobarbituric acid(TBA) values were fluctuated during storage as a whole. Water activity(Aw) and moisture contents showed a little change according to storage temperature, but sausage color was darkened as storage time goes by as a whole, the shelf-life was predicted above 40 days at $10^{\circ}C$, below 40 days at $20^{\circ}C$, below 30 days at $40^{\circ}C$ and about 20 days fluctuating temperature $(10/40^{\circ}C)$, respectively on the basis of slime formation in sensory evaluation.

• Food Science and Preservation
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• v.19 no.3
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• pp.328-336
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• 2012

The objective of this study was to investigate the storage effects of the packaging method of blanched namul(Gosari, Torandae, Chwinamul and Siraegi). The samples were packaged with three packaging types (Vinyl packaging, sealing packaging and vacuum packaging) and were stored for 10 days at $10^{\circ}C$. The quality characteristics were evaluated via a microbiological test, hardness, pH and flavor patterns analysis. The pH values of the samples were not affected by packaging method. The total aerobic and coliform plate counts were high, in the order of vacuum packaging < sealing packaging < vinyl packaging. Vacuum packaging resulted in the highest hardness value. The flavor patterns of blanched namul by packaging type were analysed with electronic nose system equipped with 12 metal-oxide sensors, and the storage shelf life of namul was evaluated by measuring the change in volatile production. As a result, it was shown that namul in vacuum packaging had few volatile production changes with higher storage time.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.5
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• pp.706-712
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• 2011

This study was carried out to investigate the quality characteristics and microbiology of the simple preprocessed food julienne white radish and pear during storage at $4^{\circ}C$ and fordevelopment of a standard recipe. Total aerobic bacteria level were $3.20{\pm}0.08$ log CFU/g in julienne white radish and pear, and $3.00{\pm}0.14$ log CFU/g in julienne white radish (control). Coliform counts were $3.20{\pm}0.08$ log CFU/g in julienne white radish and pear and $1.84{\pm}0.17$ log CFU/g in julienne white radish. Low levels of coliform and total aerobic bacteria were detected. pH values of julienne white radish and pear increased significantly after 3days, whereas that of control increased significantly after 1day. Lightness and redness decreased during storage, whereas yellowness increased significantly during storage. During storage, hardness of julienne white radish and pear decreased after 3days, whereas that of julienne white radish decreased after 5days. According to sensory evaluation, 70% julienne white radish and 30% julienne pear showed higher score in term of taste, harmony of ingredient, harmony of sauce and overall preference. Consequently, 70% julienne white radish and 30% julienne pear was determined to the best formula and a maximum storage period of 3 days was showned to be optimal.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.1
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• pp.100-107
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• 2017

This study was conducted to evaluate the quality characteristics of got mul-kimchi during storage by type of kimchi container using a plastic ark shell. The pH level, acidity, hardness, color, sensory evaluation, and microbiological activity were performed. Kimchi containers were prepared with 0%, 2%, and 3% plastic ark shell. The pH level of 2% container samples showed no significant difference compared with that of the control, whereas pH levels of 3% container samples were significantly (P<0.05) higher than those of the control and 2% sample. Acidity was not different among treatments up to 4 weeks, whereas acidity of 3% container samples was significantly (P<0.05) lower than those of the control and 2% samples after 8 weeks. Hardness significantly decreased (P<0.05) upon 0, 2, and 3% treatments with increasing storage time, but there was no significant difference among the treatments. Hunter color L values increased in the order of 0, 3, and 2% with increasing storage time. In sensory evaluation of crunchiness, 3% container samples had significantly (P<0.05) higher crunchiness than the control. Total viable cells in the 3% container with got mul-kimchi were significantly (P<0.05) lower than those of other samples at 12 and 16 weeks of fermentation. Numbers of lactic acid bacteria in the 2% and 3% container samples were significantly (P<0.05) lower than those of the control samples after 16 weeks of fermentation. These results show that the plastic ark shell kimchi container extended storage compared with the control.