• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.5
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• pp.702-710
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• 2016

The bioactivity of soy grits cheonggukjang was enhanced by fermentation using three ${\beta}$-glucosidase-producing Bacillus subtilis strains (HJ 18-9, HJ 25-8, and HJ 18-9+HJ 25-8) for 48 h at $37^{\circ}C$. The results indicate that protease, cellulase, and a-amylase activities significantly increased (P<0.05) with increasing fermentation time. In addition, the amino-type nitrogen content of B. subtilis-fermented soy grits cheonggukjang increased to 91.0~168.0 mg% after 48 h of fermentation. Among the isoflavones in soy grits cheonggukjang, contents of ${\beta}$-glucosides or acetyl-glucosides were reduced while aglycone content increased upon fermentation. In particular, soy grits cheonggukjang fermented with B. subtilis HJ18-9 and HJ25-8 showed the largest increases in aglycone content compared to complex treatment. These results provide useful information for development starter (single and complex) as well as for production of high quality fermented soybean food.

• Korean Journal of Food Science and Technology
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• v.36 no.1
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• pp.97-104
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• 2004

Effects of sub-materials such as, ethanol, mustard, and chitosan, on enzymatic, microbial and physicochemical characteristics of kochujang were investigated during fermentation. Activity of ${\alpha}$-amylase was low in chitosan-added kochujang, whereas those of ${\beta}$-amylase and pretense did not show any remarkable difference. Viable cells of yeast and bacteria decreased in sub-material-added kochujang during fermentation, with yeast counts decreasing more rapidly in ethanol- and mustard-added kochujang than that with chitosan. Consistency of kochujang decreased during fermentation, with the highest consistency observed in ethanol-added kochujang. Oxidation-reduction potential was low in chitosan-added kochujang. Water activity of all kochujang groups decreased during fermentation with the lowest in ethanol-added kochujang. Hunter L-, a-, and b-values of chitosan-added kochujang were higher than other groups, whereas increase in total color difference of low-salt without sub-material group was lowest pH of kochujang was the highest in ethanol-added kochujang, whereas titratable acidity increased remarkably in chitosan-added group. Total sugar and reducing sugar contents of kochujang were high in ethanol-and mustard-added groups, whereas ethanol production decreased remarkably in mustard-added kochujang. Amino nitrogen content was highest in low-salt without sub-material kochujang during late aging period. Ammonia nitrogen content was lower in mustard-added kochujang. After 12 weeks of fermentation, ethanol-added kochujang was more acceptable than mustard-and chitosan-added groups in taste, color, and overall acceptabilities.

• Journal of environmental and Sanitary engineering
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• v.15 no.2
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• pp.18-26
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• 2000

In order to improve the quality of Kamju(sikhae), Korean traditional sweat fermentated rice drink, Kamju made with laboratory fermenting from both covered barley malt and that added to commercial $\alpha-amylase$ and commercial sikhae can were investigated and analyzed ad follows 1. The amylase activities in L-malt(laboraory made malt), C-malt(commercial malt) were 25,065 units, 20,498 units at $60^{\circ}C$ and when heating at $60^{\circ}C$ for one hour their heat stability was getting lower and while at $70^{\circ}C$ after 2 hours both their heat stability was under 21%. 2. The external appearance, of all samples, in beating test, flipper, springer and leaker test were excellent and good valued. On the open test of sample can, head space was 7.9~9.0mm, net weight 247~250g, 432~435g, pH 4.96-5.76, Brix 13.2~14.0 and vacuum degree was 29~35cmHg. 3. The sucrose content of sample 1~5 was 8,57~10.01% highest ammount than sample 6(0.91%) 7(0.43%) and maltose content of sample 1~5 was 0.65~1.41% lower than 6 was 7.91% and 7 was 8,36%. The good traditional flavor texture and saccharides components content of glucose of sample 1~5 was 1.09~1.51, 6(3.86%), 7(3.97%), fructose content of sample 1~5 was 0.45~0.95%, 6(2.76%), 7(2.81%), maltotriose and raffinose of sample 1~5 were 0.04~0.291, 6(0.61%), 7(2.81%), and solid content of sample 1~5(3.1~3.8) was lower than 6(10.25%), 7(10.09%). 4. The result of sensory test as measured as lemone yellow of sample 6 and milky of sample 7, and weetness, flavor, color, traditional texture and sensory value for sample 1~5(3.1~3.8) was lower degree than that for 6(4.5), 7(4.0). 5. Among the heavy metals analyzed from sample cans, tin, iron and lead content for sample 1~5 were 31.95~36.71ppm, 5.84~6.39ppm and 0.075~0.09ppm while their content of sample 6.7, tin, 32.91ppm, 32.87ppm, iron 5.51ppm, 5.41ppm and lead, 0.074ppm, 0.079ppm.

• Food Science and Preservation
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• v.22 no.4
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• pp.535-544
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• 2015

This study was conducted to investigate the changes of isoflavone composition (glycoside and bio-active aglycone) in Cheonggukjang and to evaluate its quality characteristics depending on different soybean cultivars (Daewon, Daepoong, Wooram, Hwangkeumol and Saedanback). The bioactivity of Cheonggukjang was enhanced during fermentation at $37^{\circ}C$ for 48 h. Activities of ${\alpha}$-amylase, protease, and cellulase increased significantly after 48 h fermentation (p<0.05). In addition, amino-type nitrogen and reducing sugar contents in Cheonggukjang fermented with B. subtilis increased significantly after 48 h fermentation (p<0.05). Among the isoflavones, the content of $\beta$-glucosides and acetyl-glucosides decreased, while aglycone content increased during fermentation. Especially, Cheonggukjang fermented with Daepoong cultivars showed the greatest increase in daidzein, genistein and glycitein contents. After 48 h fermentation, the contents of daidzein, genistein and glycitein in the Cheonggukjang fermented with Daepoong cultivars increased significantly up to $503.65{\pm}2.76$, $111.40{\pm}0.42$, and $633.95{\pm}6.01{\mu}g/g$ (p<0.05), respectively. Total aerobic and anaerobic cell counts increased with increase in fermentation time. Therefore, it would be beneficial for the food industry if components of Cheonggukjang could be separated and used to develop functional products.

• Food Science and Preservation
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• v.18 no.2
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• pp.171-177
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• 2011

In order to demonstrate the usefulness of Deodeok. the functions of Deodeok and the qualities of Cheongkukjang were investigated. DPPH (1.1-diphenyl-2-picryl-hydrazyl) radical scavenging activity of Deodeok extracted with 70% ethanol was higher than that of water extract. The direct antimutagenic effect of ethanol extract of Deodeok was examined by Ames test using Salmonella typimurium TA 98. The inhibition rates on ethanol extract at concentrations of 200, 1.000, 2.000, 3.000 and 4.000 ${\mu}g$/plate were 5.75, 31.38, 34.75, 53.50 and 83.75%, respectively. The inhibition rates of ethanol extract was higher over 2 times than that of water extract. The qualities including physicochemical and sensory properties of Deodeok Cheongkukjang were investigated over the following range of Deodeok levels; 5, 10, 15 and 20% (w/w). The strain used in Cheongkukjang manufacture was Bacillus sp. B-3 with the highest enzyme activities such as amylase and protease. During fermentation at $40^{\circ}C$ for 6 days. amino-type nitrogen content of Cheongkukjang containing 10% (w/w) Deodeok was more than others. When Deodeok content exceeded 15% (w/w), higher contents resulted in lesser amino-type nitrogen production. The results showed that Deodeok had influenced the growth of Bacillus sp. B-3. The L-value of Deodeok Cheongkukjang was decreased according to increasing the Deodeok contents. Sensory evaluation showed that Deodeok Cheongkukjang containing 10% (w/w) Deodeok was superior to other tested.

• 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.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.1
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• pp.52-59
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• 2005

The study was targeted to saccharify foodwastes with the cellulolytic and amylolytic enzymes obtained from culture supernatant of Trichoderma harzianum FJ1 and analyze the kinetics of the saccharification in order to enlarge the utilization in industrial application. T. harzianum FJ1 highly produced various cellulolytic (filter paperase 0.9, carboxymethyl cellulase 22.0, ${\beta}$-glucosidase 1.2, Avicelase 0.4, xylanase 30.8, as U/mL-supernatant) and amylolytic (${alpha}$-amylase 5.6, ${\beta}$-amylase 3.1, glucoamylase 2.6, as U/mL-supernatant) enzymes. The $23{\sim}98\;g/L$ of reducing sugars were obtained under various experimental conditions by changing FPase to between $0.2{\sim}0.6\;U/mL$ and foodwastes between $5{\sim}20\%$ (w/v), with fixed conditions at $50^{\circ}C$, pH 5.0, and 100 rpm for 24 h. As the enzymatic hydrolysis of foodwastes were performed in a heterogeneous solid-liquid reaction system, it was significantly influenced by enzyme and substrate concentrations used, where the pH and temperature were fixed at their experimental optima of 5.0 and $50^{\circ}C$, respectively. An empirical model was employed to simplify the kinetics of the saccharification reaction. The reducing sugars concentration (X, g/L) in the saccharification reaction was expressed by a power curve ($X=K{\cdot}t^n$) for the reaction time (t), where the coefficient, K and n. were related to functions of the enzymes concentrations (E) and foodwastes concentrations (S), as follow: $K=10.894{\cdot}Ln(E{\cdot}S^2)-56.768,\;n=0.0608{\cdot}(E/S)^{-0.2130}$. The kinetic developed to analyze the effective saccharification of foodwastes composed of complex organic compounds could adequately explain the cases under various saccharification conditions. The kinetics results would be available for reducing sugars production processes, with the reducing sugars obtained at a lower cost can be used as carbon and energy sources in various fermentation industries.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.5
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• pp.756-762
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• 2014

This study evaluated the quality characteristics of soybean fermented with several Bacillus sp., which were selected based on their high enzymatic and antimicrobial activities. Total aerobic bacterial counts of fermented soybeans with HJ5-2 ($3.00{\times}10^9CFU/mL$) were the highest among all strains. Lactic acid bacteria numbered $2.50{\times}10^2{\sim}7.30{\times}10^4CFU/mL$ in soybeans fermented with isolates. Amylase and protease activities of the RD7-7 sample were the highest among all strains. Reducing sugar and amino-type nitrogen contents of fermented soybeans with HJ18-4 (2.35%) and RD7-7 (227.96 mg%) were the highest. Total amino acid contents of the samples were 16.62~18.38%, and glutamic acid, aspartic acid, leucine, lysine, arginine were major amino acids. Oxalic acid (36.51~63.57 mg/100 g) and succinic acid (429.49~600.15 mg/100 g) were the predominant organic acid. These results provide useful information for development starter (single and complex) as well as for the production of high quality fermented soybean foods.

• Applied Biological Chemistry
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• v.8
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• pp.75-80
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• 1967

In order to investigate the change of enzyme activities during the fermentation of tobacco leaves, whole and cut leaves were treated for twenty days at $30^{\circ}C$ and $39^{\circ}C$ by the normal procedure and inoculation of yeast, respectively, and the activity of several enzymes was measured at proper intervals. 1) Alpha-amylase activity was steadily decreased with the progress of fermentation. 2) Invertase and catalase activities were steadily decreased until the mid of the period, and then increased again toward the end of the fermentation. The latter enzyme activity showed more marked change than the former. 3) Most of the polyphenol oxidase activity were decreased abruptly in the early stage of the fermentation, and thereafter leveled down slowly. 4) Peroxidase activity was detected throughout the fermentation but no remarkable change was observed. 5) Protease activtty was not detected through the fermentation period.

• Food Science and Preservation
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• v.21 no.1
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• pp.121-128
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• 2014

This study was conducted in order to investigate the change of isoflavone composition (glycoside and bio-active aglycone), and to evaluate the quality characteristics of Cheonggukjang, which was prepared by different bacillus strains. After the 48-hour fermentation, the contents of daidzein, genistein, and glycitein in the Bacillus subtilis HJ18-3 have significantly increased up to approximately $89.06{\pm}3.59$, $10.36{\pm}0.28$, and $101.37{\pm}3.67ug/g$, respectively. The contents of daidzein, genistein, and glycitein in the Bacillus subtilis KACC 15935 were $38.88{\pm}5.39$, $12.58{\pm}2.14$, and $80.13{\pm}0.71ug/g$, respectively. The original content of daidzein was 3.96 ug/g, while genistein and glycitein were not measured. However, the contents of daidzen and genistein in HJ18-3 and in KACC 15935 were decreased. The ${\alpha}$-Amylase and cellulase activities of Chungkookjang in HJ18-3 were higher than in the KACC 15935. The contents of Chungkookjang in HJ18-3 were $29.70{\pm}11.66$ and $4861.3{\pm}388.07unit/g$, respectively. The amino type nitrogen contents and ammonia type nitrogen contents of Chungkookjang in KACC 15935 were higher than in the HJ18-3. These results suggested that it could be used to increase the bioactivity via fermentation with the Bacillus subtilis possessing a ${\beta}$-glucosidase activity with a view towards the development of functional foods.