• Korean Journal of Food Science and Technology
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• v.12 no.4
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• pp.272-277
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• 1980

The tolerance of useful bacterial spores to the conditions of tablet making, specifically, the destruction of bacterial spores upon compressional pressure was investigated. The damage of bacterial spores occurred mainly during the tabletting. The bacterial spores obeyed a logarithmic destruction rate upon compressional pressure. The spore destruction rate was dependent upon the strains of microorganism. The Decimal Reduction Pressure, designated as P-value, were $2.9\;ton/cm^2$, $2.6\;ton/cm^2$ and $2.1\;ton/cm^2$ for the spores of Bacillus subtilis, Bacilus coagulans and Clostridium butyricum, respectively, and $1.7\;ton/cm^2$ for the vegetative cell of Streptococcus faecalis. The spore destruction upon compressional pressure was influenced by the type of filler. The P-value of the spore of B. coagulans was $2.8\;ton/cm^2$ in the lactose filler, but $2.0\;ton/cm^2$ in the starch filler. The number of viable spores was inversely proportional to the hardness and density of tablet, in case that the same type of filler was used. The starch filler, which resulted in the lower hardness and lower density of tablet, caused higher spore destruction rate compared with the lactose filler.

• Food Science of Animal Resources
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• v.25 no.1
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• pp.92-97
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• 2005

This study was carried out to determine the storage, cryotolerance, heat and drying resistance, when Lactobacillus acidophilus CT 01 isolated from preweaned piglet feces growing at suboptimal temperature. L. acidophilus CT 01 suboptimal temperature incubated for 48 hours had the slowest growth rate at 22℃ but the highest viable cell number after 36 hours at 22℃, with 1.3×10/sup 9/ CFU/mL. In case of 4 and 20℃ storage, the suboptimal temperature incubated groups had a viability higher than the control (p<0.01). The cryotolerance of suboptimal temperature incubated L. acidophilus CT 01 was a higher than the control (p<0.01). When L. acidophilus CT 01 was heat treated at 60℃ for 15 minutes and 30 minutes, the suboptimal temperature incubated L. acidophilus CT 01 at 22℃ had a viability higher more than the control (p<0.01). L. acidophilus CT 01 incubated suboptimal temperature was inoculated by 30% to the carrier, and dried at 50℃ for 12 hours had the highest viability in the suboptimal temperature incubated L. acidophilus CT 01 at 28℃.

• Korean Journal of Food Science and Technology
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• v.35 no.4
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• pp.752-755
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• 2003

The antimicrobial activity of fresh garlic juice against Escherichia coli O157:H7 was investigated. When E. coli O157:H7 was cultured for 18 hr in the trypticase soy broth containing 1%, 3%, and 5% garlic juice, viable cell number of E. coli O157:H7 was reduced to $2.3{\times}10^2\;CFU/mL$ at 5% from $7{\times}10^8\;CFU/mL$ at the non-treated culture, respectively. The inhibitory effects of the ground beef treated with 3%, 6%, and 10% garlic juice against E. coli O157:H7 was significantly enhanced with approximate 2 log-reduction compared to that of ground beef without garlic. There was no significant difference in the inhibition of E. coli O157:H7 among the groups with different amounts of garlic juice (p<0.05). These results suggest that garlic juice may function well as a natural preservative in food system.

• Korean Journal of Food Science and Technology
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• v.35 no.2
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• pp.166-172
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• 2003

Changes in the number of microorganisms, chemical composition, and sensory quality of chungkukjang by gamma-irradiation up to 120 kGy were investigated. The total viable cell counts in chungkukjang irradiated with 10 kGy decreased from $10^9\;CFU/g$ of the control to $10^5\;CFU/g$. Proximate chemical composition and pH of chungkukjang were not much affected by irradiation. Acidity of chungkukjang decreased by irradiation with over 20 kGy. Fatty acid contents of chungkukjang irradiated under 20 kGy were the same as those of the nonirradiated ones. Polyunsaturated fatty acids content, decreased at over 40 kGy. The color and odor of chungkukjang were not significantly affected by irradiation up to 20 kGy. Unpalatable odor (p<0.01), off-flavor (p<0.001), and fish-odor (p<0.001) increased, and brown intensity (p<0.05) and acceptability (p<0.001) decreased at over 20 kGy. Results indicate 20 kGy is sufficient to decrease the microbial count of chungkukjang and prevent decrease in the content of polyunsaturated fatty acids.

• Korean Journal of Food Science and Technology
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• v.33 no.5
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• pp.589-595
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• 2001

Effect of anti-microbial agents, such as alcohol, garlic, chitosan, K-sorbate, or mustard, or pasteurization on the quality of traditional kochujang was investigated during storage at $30^{\circ}C$ for 24 weeks. Water activities of kochujang decreased after 12 weeks of storage. Consistency increased during storage and highest consistency of kochujang was obtained by the addition of mustard or garlic. Hunter a- and b-values decreased linearly as storage time passed. The degree of increase in total color difference$({\Delta}E)$ of alcohol added group was the highest among the tested anti-microbial agents. Gas was rapidly produced in the control and chitosan added group of kochujang. Capsanthin content decreased more rapidly in the group of alcohol, garlic or mustard added kochujang than the other group. Viable cell counts of yeast and aerobic bacteria in kochujang increased up to 12 weeks of storage, and then decreased slowly. The number of yeast was low in K-sorbate or alcohol added group. Activity of ${\alpha}-amylase$ decreased during storage, but that of ${\beta}-amylase$ increased in alcohol, garlic, K-sorbate added or pasteurized kochujang. Protease activities did not show any remarkable differences in the groups of tested during storage.

• Korean Journal of Food Science and Technology
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• v.32 no.2
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• pp.410-416
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• 2000

Changes in microflora and enzyme activities of three kinds of kochujang were investigated during 6 months of fermentation. Three different kinds of kochujang were prepared using Aspergillus oryzae, Aspergillus oryzae plus Bacillus licheniformis and Aspergillus oryzae, Bacillus licheniformis plus Saccharomyces rouxii. The pH of kochujang showed a slight decrease during fermentation. The number of mold and bacteria increased up to 30 days of fermentation and then decreased rapidly thereafter and the numbers of yeast increased after 30 days of fermentation. The viable cell counts of anaerobic bacteria increased remarkably up to 30 days of fermentation and then decreased to 60 days of fermentation. The activities of ${\alpha}-$, ${\beta}-\;amylase$ and protease were the highest in kochujang prepared with Aspergillus oryzae plus Bacillus licheniformis.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.4
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• pp.588-594
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• 1997

In this study, the shelf-life of Kochujang during storage was predicted through physicochemical and sensory analyses. Amino nitrogen, lightness, characteristics of surface color, pH and number of viable cell counts in Kochujang decreased during storage, while ammonia nitrogen, titratable acidity and viscosity increased. Among the physicochemical analyses, amino nitrogen content exhibited the highest correlation with sensory score. The marginal amounts of amino nitrogen was 170.6mg%. Degradation rate of amino nitrogen was a first order reaction. Q$_{10}$-value and the activation energy of Kochujang during storage were 1.80 and 8.6kca1/mol, respectively. The shelf-life Predicted of Kochujang at each storage temperature was calculated. The shelf-life predicted was 467 days at 1$0^{\circ}C$, 261 days at 2$0^{\circ}C$ and 133 days at 35$^{\circ}C$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.7
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• pp.912-918
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• 2006

This study examined the improvement of bread quality with Curcula longa and Glycyorrhiza uralensis extract (CGE). When counted, the viable cell number in bread with 5% of CGE dramatically was decreased by about 1 log cycle as compared to that of bread without CGE. With regard to oxidation, the content of malonaldehyde diminished in breads with increasing amounts of CGE. Breads with 1 and 5% of CGE were shown to have the highest antioxidative effect. The moisture contents of bread with CGE and bread without CGE were not much different during the early storage period. After six days of storage, however, the moisture contents of bread without CGE and bread with 0.5% of CGE decreased about 16%. On the other hand, the moisture contents of bread with 1% and 5% of CGE did not change dramatically. Their moisture content was decreased by only 4% during the same storage period. Although color, lightness and redness gradually diminished with increasing amounts of CGE in bread, conversely yellowness increased. In the sensory evaluation, bread with 0.5% and 1% of CGE scored the highest: 3.66 and 3.67 out of 5, respectively. Bread with 5% of CGE scored the lowest of the various bread tested. From these results, the addition of 1% CGE in bread had a good effect on improvement of preservation and development of quality.

• Food Science and Preservation
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• v.12 no.4
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• pp.395-401
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• 2005

This study was carried out to investigate the changes in the fermentation characteristics of Kimchi prepared with various salts (Korean solar salt, Chinese solar salt, washed and dehydrated salt, purified salt and a processed salt). Acidity appeared to increase most rapidly in Kimchi prepared with Korean solar salt and reached higher level. Total microbial count slowly increased at the beginning of fermentation and reached maximum on 6 days, then decreased slowly. The number of lactic acid bacteria was rapidly increased up to $4{\sim}6$ days, and thereafter decreased slowly. In conclusion, any significant differences in fermentation characteristics analyzed was not observed in Kimchi prepared with various salts except acidity.

• Food Engineering Progress
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• v.14 no.4
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• pp.359-366
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• 2010

Large-scale preparation steps of antithrombotic materials from wood ear mushroom (Auricularia auricular-judae) were established as follows. Grounded dry wood ear mushroom was extracted with 75% ethanol and its precipitate was extracted with $76^{\circ}C$ water for 2 hr followed by filter pressing. The filtrate was then concentrated by vacuum and extracted with 80% ethanol, and the resulting precipitate was then freeze-dried. The formula of the product was determined using consumer susceptibility tests as follows; mushroom extract 90.5%, high fructose corn syrup 2.0%, $\beta$-cyclodextrin 1.5%, fructo-oligosaccharide 2.0%, pear puree 4.0%. When the packed products were stored at 25, 37, or $45^{\circ}C$ for 8 weeks, there were no noticeable changes in water activity, moisture content, pH, and acidity. The viable cell number of total bacteria was slightly increased during the storage period at 25 and $37^{\circ}C$, The total bacteria were not detected in the product when stored at $45^{\circ}C$. When the product was injected intravenously into rat at the level of 1,000 mg/kg, antithrombotic activities such as activated partial thromboplastin time, thrombin time, prothrombin time, and FIB were increased when compared with the control group. When the product was administrated orally into rat at the level of 500 mg/kg, it showed the same antiplatelet activity to aspirin.