• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.3
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• pp.461-466
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• 2010

A cylindrical UV sterilization system was developed to decrease microorganisms in centrifuged Takju (CT). CT was run through 110 strips of honey comb type-teflon tubes and 9 UV lamps (1395 W) were equipped between teflon tubes. The optimum sterilization condition of CT was fixed for 1.5 min at 2 L/min in overall quality aspects; also, 5~6 log cycle decrease of viable cell numbers of total bacteria and yeast was observed at this operating condition. Quality changes of UV-sterilized CT were examined by UV irradiation of CT followed by storing at $30^{\circ}C$ for 8 days. To evaluate quality changes of UV-sterilized CT, pH, amino nitrogen content, acidity, reducing sugar content and viable cell numbers of total bacteria and yeast were measured. The growth of yeast and bacteria was retarded, showing around $10^8\;CFU/mL$ even after 4 days and $10^8\;CFU/mL$ after 6 days, respectively. Also, UV sterilized CT showed no changes in pH, titratable acidity, and amino nitrogen content during storage except reducing sugar content. UV sterilization did not cause significant difference in L, a, and b values between CT and UV-sterilized CT over the storage period.

• Food Science and Preservation
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• v.9 no.1
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• pp.28-35
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• 2002

This study was conducted to evaluate the quality characteristics of different soy sauces. The soybean sauces brewed tty the A. oryzae koji(SAO), M. pilosus-1 koji(SMP) and the mixture of 50% M. pilosus-1 koji(SAM) during 90 days fermentation. Total nitrogen contents of the SAM, SAP and SMP were 13.6%, 1.15% and 1.22%, respectively. Content of amino type nitrogen in SAM was 0.78%, and the content was higher than those of SAO and SMP. Total free amino acid contents of SAO, SMP and SAM were 533.8, 732.4 and 807.3 mg/100 mL. The highest contents of free, amino acids were glutamic acid(65.20 mg/100 mL) in SAG, alanine(101.42 mg/100mL) in SMP, glutamic acid(130.52 mg/100 mL) in SAM. The highest activities of pretense and ${\beta}$-amylase showed in SAM, and the lowest activities of ${\alpha}$-amylase and glucoamylase were in SAO and SMP respectively. Hue angle values showed 56.3 in SAO, 29.0 in SMP and 32.2 in SAM. Monacolin K contents, as inhibitor of cholesterol bio-synthesis were 6.21 $\mu\textrm{g}$/mL for SMP and 3.10 $\mu\textrm{g}$/mL for SAM, and the inhibitory activities of SMP ane SAM aginst HMG-CoA reductase were 21.5 md 10.2%, respectively. Sensory scores for color, flavor, savory taste and overall taste of SAM was higher than those of SAO and SMP.

• Food Science and Biotechnology
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• v.17 no.3
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• pp.527-533
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• 2008

For preparation of high quality kochujang by the traditional fermentation method, 4 types of kochujang were prepared with brick- or grain-shaped meju fermented with different strains (Aspergillus sojae, Aspergillus oryzae+Bacillus subtilis). After 100 days of fermentation at $25^{\circ}C$, the moisture, pH, salt, and ethanol content of kochujang were 40.52-43.20%, 4.71-4.82, 8.7-9.1%, and 0.75-0.94%, respectively, showing slight differences according to the strains and shapes of meju. Titratable acidities were slightly increased for up to 60 days of fermentation. The amino-type nitrogen content of kochujang prepared with brick-shaped meju (A. oryzae+B. subtilis) was the highest (164.20 mg%) among all of the kochujang types. The redness (a) value of kochujang prepared with brick-shaped meju (A. sojae) were higher (19.08) than those of other treatments (18.37-18.59). Sensory evaluation of kochujang prepared with grain-shaped meju (A. sojae) showed the highest scores for color and overall acceptability, 'at $6.43{\pm}1.87$ and $6.29{\pm}1.44$, respectively. It was estimated that high quality kochujang could be made by using meju fermented with selected strains.

• The Korean Journal of Food And Nutrition
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• v.26 no.2
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• pp.266-272
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• 2013

This study investigated the quality characteristics of black soybean paste(Daemacjang) with black soybean content and salt concentration. The total acidity increased as the pH decreased during fermentation period. The amino-type nitrogen content of all samples increased significantly during fermentation time. Total cell counts was not significantly different during fermentation, and mold counts decreased at 3 log cycles. The cell counts of lactic acid bacteria decreased approximately 2 to 3 log cycles in 10% salt concentration (treat B and C), and were not detected in treat A and D. Total polyphenol contents of treat A, B, and C were 42.77%, 52.99% and 52.95% during fermentation up to 70days, respectively, which was higher than D (39.86%). In a sensory evaluation, treat B showed the highest scores for overall acceptability.

• Journal of the Korean Society of Tobacco Science
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• v.1 no.1
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• pp.1-8
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• 1979

For the preliminary experiments of mass Production of tobacco cells in tank culture, the effects of nutritional conditions on the growth of suspended cells were investigated ; 1. The tobacco cell growth was affected by concentrations of sucrose or inorganic phosphate, type of nitrogen source, and plant hormone, especially 2, 4-D. 2. The optimum level of sucrose concentration was 3% and the level of inorganic phosphate was 0.3mg /ml, which was about twice as high as the level of Linsmaier - Skoog medium. 3. The best growth was observed when the ratio of nitrate nitrogen to ammonium nitrogen was 2 : 1, where the total nitrogen content was equal to that of nitrogen source. 4. To find out the mechanism of promotive effects of 214-D and inorganic phosphate on the tobacco cell growth, the respiration and metabolism of $^{14}\textrm{C}$-91ucose were investigated. Addition of 2, 4 -D in culture medium increased if 2, 4-D (0.2ppm )was added to medium or the level of inorganic Phosphate was raised 2.5 times as high as standard. In cultures with high inorganic phosphate and 2, 4-D, the absorbed 14C-glucose was converted to amino acids and organic acids rather than remained as sugars.

• Korean Journal of Food Science and Technology
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• v.32 no.6
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• pp.1350-1357
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• 2000

Traditional Kochujang was prepared adding horseradish or mustard powder to repress the gas formation which used to cause swelling problem during distribution. The koji for Kochujang was prepared by the strains which had high amylase and protease activities with superior flavor. The gas production from Kochujang during fermentation at $25^{\circ}C$ was ceased after stopping yeast growth completely by bactericidal components from $0.6{\sim}1.2%(w/w)$ of horseradish or mustard addition. Total viable bacterial count was not affected by adding horseradish or mustard. The amino type nitrogen content in Kochujang, which was one of the most important parameters in quality of Kochujang, increased continually during fermentation. The Kochujang fermented by P-2 isolate and added with mustard was significantly higher in amino type nitrogen content than other treatments after 120 days' fermentation. ${\alpha}-Amylase$ activity was very low while ${\beta}-amylase$ activity was high in Kochujang fermented by adding horseradish and mustard powder. The protease(acid and neutral) activities gradually increased by fermentation with no difference between treatments. The color and flavor were not different, but overall palatability of the Kochujang evaluated by sensory test showed significantly high rank in Kochujang fermented by P-2 isolate and with horseradish.

• Korean Journal of Food Science and Technology
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• v.23 no.5
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• pp.599-604
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• 1991

The physico-chemical properties of viscous substances extracted from chungkook-jang were investigated. The crude protein content of the viscous substance was approximately 61% and 32% of the crude protein content was amino type nitrogen. The contents of glutamic acid in amino acids and potassium in minerals of viscous substances were more higher than those of raw soybean and chungkook-jang. The viscosity of 5% viscous substance solution was higher than that of 15% sucrose solution. The transmittance of viscous substance solutions from Bacillus natto and Bacillus subtilis was lowest at pH 5.0, the absorbances were lowest at pH 5.5 and pH 4.0, respectively. The fibrinolytic activity of viscous substances by B. natto and B. subtilis was 0.438 and 0.163 unit/mg protein, respectively. Though viscous substances were heated for 5 min and 30 min at $100^{\circ}C$, 90% of and 45% the fibrinolytic activity was remained, respectively.

• Applied Biological Chemistry
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• v.42 no.4
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• pp.283-287
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• 1999

This study was carried out to select the most suitable soybean cultivars for the quality kanjang preparation. Six cultivars of soybean, Taekwangkong, Kumjungkong #1, Sinpaldalkong #2, Hwangkeumkong, Danbaegkong and Danyeobkong, were used as the raw materials for kanjang preparations. Grain type meju was prepared by the inoculation of Bacillus subtilis var. globigii seed culture on the cooked soybean of respective cultivar and cultivation at $30^{\circ}C$ for 10 days. Two month matured respective kanjang mash, which was prepared by mixing meju and 20% salt brine in the ratio of 1 : 3, was separated and the liquid portions were used as kanjang samples for this work. The highest crude protein content of 47.5% was obtained from Danbaegkong cultivar among six soybean cultivars tested. High sugar soybean cultivars were found to be Kumjungkong l and Danbaegkong and the content 15.87% and 13.33% respectively. The highest total nitrogen(TN) content of 1.18% was shown from Danbaegkong kanjang. Although the major free organic acid in kanjang was found to be succinic acid, no significant differences in free organic acid and sugars content were observed among cultivars. The highest free total amino acids(TA) and glutamic acid(GA) content in kanjang was observed to be 3365 mg% and 734.44 mg% respectively from Danbaegkong kanjang. Danbaegkong cultivar soybean which was shown to contain the highest crude protein was found to be the most suitable one for the preparation of quality kanjang with high TN, GA content and GA/TA ratio.

• Food Science and Biotechnology
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• v.15 no.4
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• pp.549-554
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• 2006

To standardize a manufacturing method and improve the quality of traditional kochujang, eight-types of meju with different shapes (brick, grain) were prepared using Aspergillus oryzae (A.o) or Aspergillus sojae (A.s) alone or in combination with Bacillus subtilis (B.s). The physicochemical characteristics and enzyme activities of the various meju were compared during fermentation for 12 days at $28^{\circ}C$. The moisture content of both the brick- and grain-shaped meju were gradually decreased from an initial content of 50.47 to 54.89% to a content of 12.91 to 16.25% on day 12 of fermentation. The neutral protease activities of the brick-shaped meju ranged from $1.19{\pm}0.12$ to $1.25{\pm}0.28\;unit/mL$, and were similar for all treatments. The ${\alpha}$-amylase activities in A.s+B.s treatment of brick-shaped and grain-shaped meju were the highest, $11{\pm}0.6$ and $9{\pm}0.7\;unit/mL$, respectively. The ${\beta}$-amylase activities ranged from $1.53{\pm}0.01$ to $1.56{\pm}0.02\;unit/mL$, and were similar for all treatments. The amino type nitrogen content of A.o+B.s brick-shaped meju was the highest, $0.39{\pm}0.03%$. We confirmed that the brick-shaped meju prepared with A. oryzae and B. subtilis could be used to prepare traditional kochujang to improve the quality of the product.

• The Korean Journal of Community Living Science
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• v.21 no.4
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• pp.571-579
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• 2010

Jeupjang has long been considered only a local delicacy. So, it has gradually been forgotten because its name and definition have not been established. This study was performed in order to provide some basic data by comparing the general components, color, free amino acids, free sugar, organic acids and antioxidant activities between commercial Jeupjang(GG, GD, JM, NJ, NS). Moisture contents, crude protein, crude fat and crude ash contents of Jeupjang were 48.07~61.77%, 4.08~10.53%, 3.92~4.64%, and 3.63~9.95%. pH, titrable acidity and salt in Jeupjang were 4.32~5.50, 9.37~14.82 mL(1N-NaOHmL), and 3.27~8.90%. Amino-type nitrogen content is 42.05~ 138.83mg%. Lightness(L), redness(a) and yellowness(b) values in color of Jeupjang were10.04~21.89, 18.92~28.80, and 17.16~37.56. The total content of free amino acids in commercial Jeupjang ranged from 35.22mg% to 306.02mg% in which it showed wide variation among samples. The major free amino acids were glutamic acid, aspartic acid, alanine and proline. The major free sugars were fructose(0.31~1.60%), glucose(6.20~ 13.61%) and maltose(7.34~10.01%). The major organic acids were succinic acid(29.08~ 103.62 mg%) and citric acid(3.08~108.69 mg%). Total polyphenol contents were from 1.16 mg/g to 1.78 mg/g, DPPH radical scavenging activity is from 0.57 AEAC to 1.53 AEAC and ABTS radical scavenging activity is from 1.58 AEAC to 2.85 AEAC. This result might cause the differences of soybean composition, processing methods and brewing periods. For the succession of traditional fermented food such as Jeupjang, quality standards are required. To this end, the standardization of manufacturing processes must be followed.