• Korean Journal of Food Science and Technology
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• v.29 no.6
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• pp.1144-1150
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• 1997

Volatile flavor components of soybean koji kochujang made from a glutinuous rice by improved method were analyzed by using a purge and trap method during fermentation, and identified with GC-MSD. Fifty-six volatile flavor components including 16 alcohols, 15 esters, 7 acids, 4 aldehydes, 5 alkanes, 3 ketones, 1 benzene, 1 alkene, 2 phenol and 2 others were found in improved kochujang. The number of volatile flavor components detected immediately after making kochujang were 32 and increased to 46 components after 30 day of fermentation. The most number 55 of volatile flavor components were found after 90 day of fermentation. Thirty-one kinds of volatile flavor components were commonly found through the fermentation period 9 alcohols such as 2-methyl-1-propanol, ethanol, 3-methyl-1-butanol, 8 esters such as methyl acetate, ethyl acetate, 2-methylpropyl acetate, 3 aldehydes such as butanal, acetaldehyde, furfural and 11 othesrs. Although the various types of peak areas (%) of volatile flavor components were shown in kochujang during the fermentation days, ethanol. ethyl acetate, ethyl butanoate, 2-methylpropyl acetate, 2-methyl-1-propanol and 3-methyl-1-butanol were mainly detected during fermentation. Those might be the major volatile flavor components in kochujang made by improved method. Peak area of ethanol was the highest one among the volatile flavor components at immediately after mashing and 90 day while ethyl acetate showed the highest Peak area after $30{\sim}60$ day of fermentation and 3-methyl-1-butanol showed the highest peak area after $120{\sim}150$ day of fermentation.

• Korean Journal of Food Science and Technology
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• v.37 no.4
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• pp.618-623
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• 2005

Kimchi was prepared with 2.5% and 5% Monascus purpureus Koji(MPK) paste(20%), fermented at $10^{\circ}C$ for 15 days, and sampled at 3-day intervals during storage. Samples were extracted using 80% ethanol. Ethanol extracts of kimchi prepared with MPK paste (MPK kimchi extracts) and control kimchi extracts at 1mg/mL showed 40% decrease in proliferation of cancer cells, such as AGS, KATOIII, HepG2, and Hela. MPK kimchi extracts showed highest cytotoxic effect against cancer cells compared with control at 2mg/mL. Antibacterial effect of MPK kimchi extracts decreased during fermentation, and was higher than that of control kimchi extracts during fermentation, particularly after six days. The 5% MPK kimchi extracts showed higher antibacterial activity against Escherichia coli O157:H7 and Vibrio parahaemolyticus than other groups. Results indicate kimchi added with M. purpureus Koji paste has stronger antibacterial and anticancer effects in vitro than control kimchi.

• Korean Journal of Food Science and Technology
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• v.17 no.5
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• pp.350-354
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• 1985

For the purpose of studying the possibility to use the barley as a raw material in vinegar manufacturing process, several factors related to the fermentation of acetic acid were investigated. The optimum quantity of sweet liquor prepared by koji method in medium was 30-40%. When koji of A. oryzae, commercial enzyme products and malt were used for the saccharification of the barley, the production rates of acetic acid during log period were 0.056%/hr, 0.025%/hr, 0.03896/hr and lag period were 22 hours, 48.5 hours and 25 hours, respectively. These results indicate that the saccharifying method using koji of A. oryzae is superior to that by the commercial enzyme products or malt for the acetic acid fementation. The optimum initial acidity was 2% and the proper initial ethanol degree were 4-6% in metium. In a submerged culture process using a jar fermentor, lag period was 15 hours, and acetic acid fermetation period was about 45 hours. In the sensory test of barley vinegar and commercial vinegar of the market, barley vinegar was superior to the vinegar in market with respect to tastes.

• Korean Journal of Food Science and Technology
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• v.21 no.5
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• pp.649-654
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• 1989

The color distribution of fish sauces was studied by using the change in log absorbance per 100nm as a parameter of color tone. A linear relationship was found between the logarithm of absorbance (log A) and wavelength at 450 nm to 650 nm in the color of fish sauces. Change in log A per 100nm $({\Delta}A)$ in the color of the fish sauce products was in the range of 0.55 to 0.59. Absorbance at 450 nm (A 450) of the fish sauce treated with soy sauce koji was high in comparison with A 450 of the fish sauce treated by pronase and control. The color of fish sauces treated with soy sauce koji was dark reddish orange, and was similar to the color of soy sauce. A 450 of every fish sauce increased with the progress of fermentation but ${\Delta}A$of the fish sauces slightly increased at the beginning of fermentation and then decreased at the end of fermentation. In the results of sensory evaluation for the flavor of fish sauce products, the fish sauce product treated with soy sauce koji that 20% salt was added at the first stage was the molt desirable in the strength of flavor, tastefulness and after taste, and the fish sauce was also the best in acceptability.

• Applied Biological Chemistry
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• v.22 no.2
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• pp.91-96
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• 1979

Several herbs were tested for their antimicrobial activities during preservation of soy sauces. The herbs which resulted in retarded growth of film yeasts were extracted and added to various media such as koji-extract agar, buion-peptone agar to elucidate effects on the growth of film yeasts, Aspergillus oryzae and Bacillus subtilis. The results obtained were as follows: 1) Addition of phellodendron powder resulted in retarded formation of film in fermented soy sauces. Film was produced after 2 days without addition of the phellodendron powder. However, formation of film was observed after 8 days when 0.5 per cent of the phellodendron powder was added, and after 12 days when 1.0 per cent of the powder was added to fermented soy sauce. 2) For the amino acid soy sauce, formation of film was retarded for 6 days by 0.5 per cent of the pow der and for 8 days by 1.0 per cent of the powder. 3) Repression of film yeasts by addition of helenii and camphora powder was recognized respectively, but other herbs were appeared to have no detectable effects. 4) Growth of film yeast and Asp. oryzae way, retarded for 5 days on koji-extract agar plates which contain 0.5 per cent of phellodendron extract. Bac. subtilis also showed retarded growth for 5 days on buion-peptone agar plates containing the same amount of the extract. 5) Retarded growth of film yeast for 5 days was obtained when grown on koji-extract agar plates containing 15 per cent of sodium chloride and 0.3 per cent of phellodendron powder, however, no growth of Asp. oryzae was obtained on this concentration of sodium chloride. Growth of Bac. subtilis was repressed for 5 days on buion-peptone agar plates which contain 15 per cent of sodium chloride and 0.1 per cent of phellodendron powder.

• Applied Biological Chemistry
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• v.31 no.2
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• pp.154-161
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• 1988

In order to improve the quality of amino acid soysauce, this experiment was carried out as follows; koji added amino acid soysauce(KAAS) was prepared by addition of defatted soybean and meal koji into amino acid soysauce containing $0.5%{\sim}1.5%$ of total nitrogen. Various physicochemical characteristics of KAAS during aging were determined. Total nitrogen, amino-nitrogen, specific gravity, pure extract, total acidity and color were high in KAAS at high total nitrogen. After one month aging, reducing sugar was high in KAAS at high total nitrogen, but pH was high in KAAS at low total nitrogen. Ethyl alcohol was 2.07% in KAAS at 0.5% of total nitrogen after five months aging and 1.4% in KAAS at 1.5% of total nitrogen. Levulinic acid and lactic acid were high in KAAS at low total nitrogen. The results obtained above summarized as the quality of KAAS were highly good at $0.5{\sim}0.7%$ of total nitrogen after two or three months aging.

• Korean Journal of Food Science and Technology
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• v.4 no.2
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• pp.106-111
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• 1972

The possibility of substituting raw materials for soy sauce by corn gluten was studied by measuring the amylase and proteolytic activities of koji. Also optimum conditions of koji making were determined. It was found that substitution of up to 30% of the defatted bean content (or 15% of the total bean and wheat content) with corn gluten yielded a good quality of soy sauce. Use of more than 15% corn gluten (based on total bean and wheat content) yielded a soy sauce of poor taste and low nitrogen content even though corn gluten has a high nitrogen content. This drop in nitrogen was attributed to the low enzyme activity in koji containing more than 15% corn gluten and the difference in availability of nitrogen in bean compared to corn gluten.

• Journal of computational fluids engineering
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• v.13 no.4
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• pp.96-106
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• 2008

We review a series of studies on turbulent skin friction drag reduction in wall-turbulence recently conducted in Japan. First, an identity equation relating the skin friction drag and the Reynolds shearstress (the FIK identity) is introduced. Based on the implication of the FIK identity, a new analytical suboptimal feedback control law requiring the streamwise wall-shear stress only is introduced and direct numerical simulation (DNS) results of turbulent pipe flow with that control is reported. We also introduce DNS of an anisotropic compliant surface and parameter optimization using an evolutionary optimization technique.

• Proceedings of the Korean Magnestics Society Conference
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• 2007.05a
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• pp.71.1-71.1
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• 2007

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.7-8
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• 2002

It is a time to introduce a concept of lubrication to space systems. Minimum amount of lubricant should be supplied to a contact interface instead of preparing too much lubricant on surfaces of the earth. In situ controllable lubrication method is wanted to overcome unexpected tribo-troubles in space. Tribo-coating, which forms a thin solid film in nm-scale by vacuum deposition during friction, is a promising lubrication method for space.