• Korean Journal of Food Science and Technology
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• v.40 no.4
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• pp.400-405
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• 2008

The effects of different starter cultures on the fermentative characteristics of cheonggukjang were examined by using three Bacillus strains. The strains included Bacillus subtilis KCTC 1021 as a control, Bacillus sp. Kn-10 (Kn-10) isolated from a commercial cheonggukjang, and Bacillus sp. B-59 (B-59) isolated from rice straw. There were no significant differences in pH or viable cells among the different cheonggukjang samples during fennentation for 72 hr at $40^{\circ}C$. However, the sample prepared with B-59 had higher slime content and protease activity than the controls and Kn-10 samples. DPPH free radical scavenging activity was higher in the B-59 sample and lower in the control and Kn-10 samples when compared to steamed soybeans after fermentation for 72 hr at $40^{\circ}C$. The total amino acid contents the cheonggukjangs were 34869.98 mg% (B-59), 34481.89 mg% (control), and 31791.09 mg% (Kn-10). Glutamic acid and lysine contents were higher in the B-59 sample than in the control. Finally, the cheonggukjang fermented using the B-59 strain had improved sensory qualities such as color, taste, texture, and overall acceptability compared to the control and Kn-10 samples.

• 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.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.10
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• pp.1244-1250
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• 2008

This study was carried out investigate the effects of chungkukjang added with onion (OC) and chungkukjang (C) on the lipid and antioxidant metabolisms of hypercholesterolemic rats. Thirty-two male Sprague-Dawley rats were divided into four groups after 1-week adaptation period and were fed a normal diet, high fat-cholesterol diet (HC), HC-OC or HC-C for 8 weeks, respectively. The supplementation of HC-OC and HC-C groups significantly reduced hepatic total cholesterol and AST activity. HC-C group increased high density lipoprotein, while decreasing low density lipoprotein and AI compared with HC-OC group. Conjugated dienes of HC-C group was significantly lower than those of HC-OC group. $H_2O_2$ induced DNA damage reduced significantly in HC-OC and HC-C groups compared with high fat-cholesterol diet group. $H_2O_2$ induced DNA damage exhibited significant positive correlations with hepatic total cholesterol, AST and CD. These results suggested that supplementation of chungkukjang or chungkukjang added with onion might be helpful in preventing lipid oxidation and leukocytic DNA damage. However, the health beneficial effect has not improved by the addtion of onion in chungkukjang.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.2
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• pp.174-181
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• 2012

This research aimed to examine the isoflavonoid contents, antibacterial activities, and physiological activities of Cheonggukjang made from sword bean (CS). The effects of adding sword bean were compared with those of raw materials (RM), steamed materials (SM), and traditional Cheonggukjang (TC). In the case of the antibacterial activity on Gram-positive bacteria, the result of CS in ethanol extract was the highest in Bacillus cereus, and the result of water extract was the highest in Staphylococcus aureus. However, in the case of Gram-negative bacteria, Salmonella Typhimurium was the highest in all the extraction. Antioxidant activity and total flavonoid contents were present in the order of TC

• Journal of Life Science
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• v.23 no.4
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• pp.560-568
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• 2013

Chungkookjang was fermented by B. subtilis MC31, a ${\gamma}$-amino butyric acid (GABA) producing microorganism. The characteristics of Chungkookjang were investigated while fermenting. Twenty four amino acids were detected in Chungkookjang, leucine was the highest of them all. Total cell populations of B. subtilis MC31 phase were between log $9.52{\pm}0.5$ ~ log $9.049{\pm}0.5$ CFU/g at stationary phase. Contents of moisture, crude ash, crude protein, crude lipid and crude fiber are $61.07{\pm}0.01%$, $1.52{\pm}0.01%$, $17.66{\pm}0.04%$, $8.96{\pm}0.03%$ and 2.61%, respectively. Contents of ammonia type nitrogen, amino type nitrogen and reducing sugar were increased during fermentation at $40^{\circ}C$ for 72 hr, however those of titratable acidity and total sugar were decreased. pH was slowly alkalized during fermentation. Viscous substance and protease contents in Chungkookjang were $4.7{\pm}0.05%$ and $0.519{\pm}7.36$ g/l, apiece. When the fibrin plate and Robbin method for fibrinolytic activity were applied, B. subtilis MC31 showed high activity. These results suggested that B. subtilis MC31 is suitable to be used as a starter to enhance the quality of Chungkookjang.

• Microbiology and Biotechnology Letters
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• v.38 no.4
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• pp.467-474
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• 2010

Cheonggukjang is one of the traditional fermented soy-based foods in Korean diets. Studies in cell cultures, humans have revealed anti-hypertension, anti-stress, anticancer, antioxidant, immune enhancing effects. Angelica gigas, Rehmanniae radix, and Red ginseng are popular medicinal plants and widely used for oriental medicine. In this study a strategy had been developed to mobilize beneficial phenolics from Angelica gigas, Rehmanniae radix, and Red ginseng combined with fermented soy by Cheonggukjang fermentation for antioxidant and Type II diabetes management. The quality and functional characteristics of Chenggukjang fermented with Angelica gigas, Rehmanniae radix and Red ginseng. Cheonggukjang (CKJ), Angelica gigas Cheonggukjang (CKJ-DD), Rehmanniae radix Cheonggukjang (CKJ-RG), Angelica gigas and Rehmanniae radix Cheonggukjang (CKJ-DD+RG) and Red ginseng Cheonggukjang (CKJ-RED) were evaluated. The mobilized phenolic profile was evaluated for antioxidant activity and the potential to inhibit ${\alpha}$-amylase linked to hyperglycaemia. This research has important implications for the development of functional soy-based-fermented foods enriched with Angelica gigas, Rehmanniae radix and Red ginseng phenolics for oxidative stress - induced diabetic complications. Furthermore, Hunter's color values of 5 types cheonggukjang, lightness (L-values), redness (a-values) and yellowness (b-values) were evaluated. Free amino acid content of CKJ-RED (0.993 mg/gd. w.) showed higher than that of CKJ (0.205 mg/g-d.w.).

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.6
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• pp.899-905
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• 2003

The effects of cooked soybean and a traditional fermented soy product, chongkukjang, on blood pressure and lipid metabolism were studied in spontaneously hypertensive rat (SHR). SHRs were divided into 3 groups (n=10, male), and fed casein, powders of cooked soybean, and chongkukjang as dietary protein sources for 6 weeks. Body weight gain was not different among experimental groups, but food efficiency was increased in groups fed cooked soybean and chongkukjang diets compared to control group. Consumption of cooked soybean and chongkukjang for 6 weeks in SHR significantly suppressed blood pressure rise with aging (p<0.05). Feeding of cooked soybean and chongkukjang to SHR decreased plasma triacylglycerols (p<0.05) by 21.6% and 30.2% and LDL-cholesterol by 30.0% and 27.5%, respectively. Addition of cooked soybean and chongkukjang to the diet resulted in reduction of total lipids and triacylglycerols of liver, while consumption of cooked soybean and chongkukjang resulted in the increase of fecal cholesterol and bile acid excretions, respectively (p<0.05). Cooked soybean and chongkukjang diets down-regulated the activity of hepatic HMG-CoA reductase by 56.4% and 94.5%, compared to control, respectively. From the above-mentioned results, it can be concluded that consumption of cooked soybean and chongkukjang might be helpful in preventing cardiovascular disease by suppressing blood pressure rise and hyperlipidemia.

• Korean Journal of Food Science and Technology
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• v.23 no.4
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• pp.478-484
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• 1991

As a work on the preparation of spread type product using chungkook-jang, proximate composition and enzyme activity of chungkook-jang were analyzed and extrusion capillary viscometer was made. The effects of moisture content, oil type and content and temperature on the rheological properties of chungkook-jang spread were investigated. As the moisture content of chungkook-jang spread increased from 55% to 65%, apparent viscosity $({\eta}a)$ decreased and spreadibility and L value in Hunter color system increased. On the contrary, as the added oil content of chungkook-jang spread increased from 10% to 30%, rla increased and spreadibility and L value decreased. Specially, in case of palm olefin addition, the rla of chungkook-jang spread was more high than that of soybean oil addition. As the temperature of chungkook-jang spread increased, rla decreased and spreadibility increased. In the same conditions, the ${\eta}a$ of chungkook-jang spread increased in order of B. natto, B. natto and B. subtilis mixture and B. subtilis fermentation.

• Journal of Food Hygiene and Safety
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• v.32 no.3
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• pp.171-178
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• 2017

This study evaluated the protective effect of Chungkookjang (CKJ) extract, a Korean traditional fermented soybean product made from Bacillus species in rice straw and boiled soybean, and one of its main flavonoids, genistein, against Trp-P-1 induced cytotoxicity and DNA damage in HepG2 cells. CKJ and genistein exhibited protective effect against Trp-P-1 induced cytotoxicity and Trp-P-1 induced DNA single strand breaks. CKJ and genistein inhibited Trp-P-1 induced CYP1A1 and CYP1A2 transcription in HepG2 cells. Our results indicated that CKJ and genistein have the protective effect against Trp-P-1 induced cytotoxicity and DNA damage. Via inhibiting expression of CYP1A1 and CYP1A2. CKJ can be used as a promising functional food material that prevents the genotoxicity induced by carcinogens produced by the heat treatment of foods such as heterocyclic amines (HCAs) that cause genomic instability.

• Korean Journal of Food Science and Technology
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• v.32 no.4
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• pp.896-901
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• 2000

The effect of gamma-irradiation on the microbiological and general quality changes of the Chungkukjang was studied. Chungkukjang was prepared, irradiated at 0, 5, 10 and 20 kGy, and then stored at $25^{\circ}C$ for six weeks. The results showed that the vegetative Bacillus cell was decreased by 5 log cycles with dose of 10 kGy with 1.78 kGy of $D_{10}$ value. Also, Bacillus was nearly eliminated by 20 kGy and that survived 10 kGy gamma irradiation was decreased significantly with the duration of storage period. The formation of $NH_{2}-nitrogen$ and $NH_{3}-nitrogen$, acidification and browning were repressed by gamma irradiation. Therefore, it was considered that the Chungkukjang treated with gamma irradiation maintained better quality than that of the control with storage.