• Korean Journal of Food Science and Technology
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• v.26 no.3
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• pp.255-260
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• 1994

Four types of soybean paste(Doenjang), using traditional meju, koji, natto meju and mixture of koji and natto meju, were manufactured and fermented for 90 days. Analyzed volatile flavor components by GC-MS were confirmed to be thirty-six components including 5 alcohols, 5 aldehydes. 8 ketones, 3 acids, 9 esters and 6 miscellaneous ones. Traditional soybean paste tested had 29 components, koji and koji-natto soybean paste $26{\sim}24$ and natto soybean paste had 20 ones. Alcohol was found to be the most abundant volatile flavor components in all samples group. Traditional soybean paste had higher ratio of carbonyl to ester than any other types of soybean paste while koji-natto soybean paste had the lowest ratio of their components. The newly identified five volatile flavor components were 3-ethoxy-l-propene, dihydro-2-methyl-3-furanone. 1-hydroxy-2-propanone, 1-(2-furanyl)ethanone and 2-acethyl ethylhexanoate.

• Korean Journal of Food Science and Technology
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• v.17 no.4
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• pp.258-264
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• 1985

The energy for cooking starch prior to saccharification could be saved by fermenting raw starch into ethanol using Aspergillus niger koji of wheat bran. Optimum cultivation time to produce glucoamylase was 4 days in wheat bran medium. The rate of saccharification from uncooked corn starch were optimum at pH 3.3 and 40-$50^{\circ}C$. Corn and sweet potato starch were saccharified more efficiently by wheat bran koji than other tested starch sources. 5 days of fermentation were required for optimum yield of ethanol using a mixture of AspergiUus niger koji and dried yeast. Final ethanol yields from raw corn, sweet potato, and rice starch with agitation at the rate of 100 rpm were about 95% at $30^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.15 no.4
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• pp.326-332
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• 1983

Acorn wine was manufactured experimentally with koji inoculated the strain producing acorn tannin hydrolyzing enzyme in order to apply fungal tannase to food processing. Starch value of several Korean acorns was found to be 72.84 and the acorns were worthy of use as a carbohydrate food. Mixed koji was prepared by combination of rice and acorn powder at a ratio of 50to 50 and inoculation of Aspergillus oryzae producing amylase and Aspergillus sp. AN-11 producing tannase into the mixture in order to hydrolyze efficiently acorn tannin inhibiting alcohol fermentation in the medium, and then the mixed koji was used as a suitable koji to manufacture acorn wine. Acorn wine brewed with medium of the acorn powder treated with water and cooked and the mixed koji prepared was superior about two times to that brewed with medium of untreated acorn powder and general koji with respect to the rate of alcohol production and sugar fermentation during the 1st and 2nd brewing.

• Korean Journal of Food Science and Technology
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• v.16 no.1
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• pp.7-10
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• 1984

The three kinds of Kochujang were prepared with liquid koji equivalent to 30%, 50% and 70% of brewing water and the contents of free amino acids and free sugars during aging at $25^{\circ}C$ for 3 months were compared with those of the control group which was made from solid koji. All tested Kochujang were higher in glutamic acid, lysine and aspartic acid while lower in methionine, histidine and tryptophan. The content of total free amino acids was high in the order of control group, 70%, 50%, and 30% liquid koji group. Fructose and rhamnose were found in all groups, but glucose in only the control group and 70% liquid koji group. Fructose content was the highest of the free sugars and total free sugar content was higher in the control group and 70% liquid koji group than other groups.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.4
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• pp.369-375
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• 2018

This study investigated the effects of selected seaweeds on rice koji preparation (rice inoculated with Aspergillus luchuensis) and enzyme activity. Four types of rice koji were prepared using one of three seaweeds (0.5% laver, 0.5% kelp and 0.5% green laver) or a control for 72 h. The changes in the moisture content, water activity, pH, total mold cell count, amylase and protease activities were measured. During preparation, there was no significant difference in the moisture content among the four kojis, whereas the pH in the kojis made with either laver or green laver decreased rapidly compared with the control (P<0.05). This seemed to result from the seaweeds promoting the growth of mold cells. In terms of the activities of both amylase and protease, the koji with laver was superior. Subsequently, the amylase and protease activities of the koji made with laver were evaluated at various pHs (3 to 9), temperatures ($15-55^{\circ}C$) and NaCl concentrations (0-10%). The activities of both enzymes decreased notably at pH 9 and the protease activity decreased at temperatures above $45^{\circ}C$. Although the activities of both enzymes decreased at greater than 2.5% NaCl, activity was present at 10% NaCl.

• Food Science and Preservation
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• v.10 no.3
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• pp.360-364
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• 2003

This study was conducted to investigate the preparation possibility of Beni-koji by Monascus pilosus using dried soybean curd residue(Biji). The additional effect of water(0-50％), glucose(0-10％, w/w), monosodium glutamate(0-0.l％, w/w) and citrus peel water extracts (0-0.5％, v/w) on the pigment and monacolin K content of the Biji Beni-koji were examined. Optimal added amounts of water was 20％ of dried Biji. The highest pigment content(OD at 500 nm) of Biji Beni-koji was 1.06 in 10％ glucose, 2.26 in 0.01％ monosodium glutamate and 2.61 in 0.4％ citrus peel water extracts. The content of monacolin K in the Biji Beni-koji added with 10％ glucose, 0.01％ monosodium glutamate and 0.4％ citrus peel water extracts showed 96.38 mg％(w/w), 118.25 mg％(w/w) and 104.50 mg％(w/w), respectively.

• Korean Journal of Food Science and Technology
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• v.35 no.2
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• pp.229-234
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• 2003

Effects of Monascus koji on color, peroxide value, textural properties, microbial stability, and sensory characteristics of bologna-type sausage during storage at $4^{\circ}C$ for 22 days were studied. Addition of 2% Monascus koji resulted in attractive color and distinctly improved color retention. Lipid oxidation was effectively inhibited by lowering the level of peroxide value. Textural properties and microbial stability of the samples were not affected, whereas color was improved by the addition of Monascus koji. Utilization of Monascus koji in meat product could reduce the use of nitrite and inhibit lipid peroxidation during storage.

• Journal of Environmental Science International
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• v.29 no.3
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• pp.319-323
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• 2020

This study investigated the physicochemical properties of Pekin duck breast meat obtained from ducks fed diets consisting different types of sipjeondaebo-tang by-products and red ginseng marc with fermented red koji during storage. A total of 180 Pekin ducks (0-day old) were divided into four groups, each consisting of three replicates (15 ducks per pen). This study investigated diets with four types of treatments: control (basal diet),1% blend powder, pelleted 1% blend, and coated pellets of 1% blend; the blend was a mixture of sipjeondaebo-tang by-products powder and red ginseng marc with fermented red koji. There was no significant difference (p>0.05) in duck breast meat pH on storage days 3 and 7, TBARS on storage days 0 through 7, and DPPH radical scavenging on storage days 0 and 7. However, the pH values on storage day 0 and DPPH radical scavenging on storage day 3 were significantly different (p<0.05) in the meats from control and treated diet fed ducks. Especially, on storage day 7, the breast meat from ducks treated with different types of sipjeondaebo-tang by-products and red ginseng marc with fermented red koji showed lower TBARS values and increased DPPH radical scavenging activity compared to the control. In conclusion, addition of different types of sipjeondaebo-tang by-product and red ginseng marc with fermented red koji to 1% blend might be helpful in increasing antioxidant effects and reducing product wastage.

• Applied Biological Chemistry
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• v.22 no.3
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• pp.150-159
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• 1979

Physiological characteristics of the acetic acid bacteria isolated from the clover flower vinegar were studied and the results were summarized as follows. 1. The strains No. 1, 3, 5 were employed. By their biochemical properties observed, they seemed to belong to Acetobacter aceti. Particluarly, the strain No. 3 had the highest productivity of acetic acid. 2, When the acetic acid bacteria preincubated in $7^{\circ}Bx$ Koji extract was inoculated to $3^{\circ}Bx$ Koji extract added 0.15% yeast extract the productivity and peroxidation of acetic acid increased considerably. 3. $3^{\circ}Bx$ Koji extract added 0.005 to 0.01% of $MgSO_4{\cdot}7H_2O$ was good in the maintenance of high concentration of acetic acid. 4. Initial optimum pH of media was 6.0. 5. 2 to 4% of ethanol concentration brought a good result of the productivity and peroxidation of acetic acid in short terms.

• Applied Biological Chemistry
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• v.32 no.4
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• pp.362-366
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• 1989

For the effective use of soymilk residue(SR), by-product of soymilk production, Wheat Doenjang made of Wheat flour-SR koji(WFSR koji) and soybean was manufactured. As the results, the contents of reducing sugar were increased till 50 days in all samples and decreased thereafter during aging of the mash. The contents of amino nitrogen were prominently increased till 50 days, but increasing ratio was slightly slowdowned thereafter. The higher the mixing ratio of SR was, the less the contents of reducing sugar and amino nitrogen were. The contents of total acid were also prominently increased till 40 days, but were slowdowned thereafter and the differences among all treatments were small. As the mixing ratio of SR was increased, the yellowness and the redness were increased and the lightness was decreased in 80 days aged samples. In sensory evaluation of 90 day aged samples, control [WFSR koji 100 (WF: SR ; 100 : 0), soybean 100] was the best in soy sprout Doenjang soup. As the mixing ratio of SR was increased, the taste was dropped slightly but no significant differences were obtained between control and sample A[WFSR koji 125 (WF: SR ; 100 : 25), soybean 75], sample B[WFSR koji 150(WF: SR ; 100 : 50), soybean 50] and sample C[WFSR koji 175 (WF: SR ; 100 : 75), soybean 25], sample C and sample D[WFSR koji 200(WF: SR ; 100 : 100), soybean 0].