• Korean Journal of Microbiology
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• v.49 no.1
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• pp.71-77
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• 2013

This study was carried out to investigate the characteristics of Chungkookjang depending on different soybeans and fermentation temperatures using Bacillus amyloliquefaciens C2 isolated from homemade Chungkookjang. The highest protease activity was 854 U/g in yellow soybean Chungkookjang and 847 U/g in black soybean Chungkookjang at $35^{\circ}C$. The highest amylase activity was 3.87 U/g at $40^{\circ}C$ in yellow soybean Chungkookjang and 4.96 U/g at $45^{\circ}C$ in black soybean Chungkookjang. The highest reducing sugar content was 16.11 mg/g at $40^{\circ}C$ in yellow soybean Chungkookjang and 19.08 mg/g at $45^{\circ}C$ in black soybean Chungkookjang. The highest amino type nitrogen content was 420 mg%/g in yellow soybean Chungkookjang and 194 mg%/g in black soybean Chungkookjang at $40^{\circ}C$. The highest pH was 7.92 at $40^{\circ}C$ in yellow soybean Chungkookjang and 7.59 at $45^{\circ}C$ in black soybean Chungkookjang. The highest number of viable cell was 9.3 log CFU/g at $40^{\circ}C$ in yellow soybean Chungkookjang and at $35^{\circ}C$ in black soybean Chungkookjang. On the other hand, the lowest ammonia type nitrogen content was 225 mg%/g at $45^{\circ}C$ in yellow soybean Chungkookjang and 80 mg%/g at $40^{\circ}C$ in black soybean Chungkookjang. Yellow soybean Chungkookjang showed high protease activity, pH and amino type nitrogen, whereas black soybean Chungkookjang showed high amylase activity and reducing sugar.

• Journal of Life Science
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• v.24 no.10
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• pp.1102-1109
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• 2014

Chungkookjang has several functional properties, such as fibrinolytic activity, anticancer effects, and antioxidant effects. However, children do not like Chungkookjang because of its foul odor. A mixed culture of Bacillus subtilis MC31 and Lactobacillus sakei 383 was used to improve the production of GABA in Chungkookjang and its flavor. Most of the foul odor of Chungkookjang was removed. The slime content and viscosity of Chungkookjang fermented in the mixed culture were similar to those of commercial Chungkookjang when B. subtilis MC31 and Lactobacillus sakei 383 were inoculated in a 1:1 ratio. The maximum GABA content was obtained when Chungkookjang was fermented with B. subtilis MC31 and L. sakei 383, which was fermented at $37^{\circ}C$ for 72 hr. During the period of fermentation, the viable cell number of B. subtilis MC31 reached a peak (log 9.13 CFU/g) at six days, and L. sakei 383 reached a peak (log 6.78 CFU/g) at two days. The moisture, crude ash, crude protein, crude fat, and crude fiber contents were 61.71%, 2.05%, 17.54%, 8.36%, and 1.95%, respectively. The amino-type nitrogen content of Chungkookjang fermented by B. subtilis MC31 and L. sakei 383 was less than Chungkookjang fermented by B. subtilis MC31 alone. The ammonia-type nitrogen and reducing sugar content of the Chungkookjang fermented by B. subtilis MC31 and L. sakei 383 were higher than that of steamed soybean. The glutamic acid and GABA content detected with an amino acid analyzer were 1.40 mg/g and 0.47 mg/g, respectively. These results suggest that fermentation with B. subtilis MC31 and L. sakei 383 in a 1:1 ratio removes more of the foul odor and increases the GABA content compared with single fermentation.

• Journal of Life Science
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• v.11 no.3
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• pp.284-290
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• 2001

Changes in chemical components of small black bean chungkugjang(SBBC) added with kiwi and radish as foodstuffs to repress off-odor and enhance the quality of SBBC suring fermentation were investigated. Optimal pretreatment conditions of small black bean suitable to the fermentation of chungkugjang were 3 hrs of soaking time 1.5 times of ratio of water to black bean. 1.0 atm of high pressure, 20 min of heating time, cutting and crushing of heat-treated black bean. Moisture content of SBBC was remarkably lower than that of soybean chungkugjang(SBC) as control. Crude protein of SBBC was in the range 23.37∼25.71% and higher than that of SBC, Crude lipid of SBBC was lower than that of SBC. Crude lipid of SBBC added with kiwi and radish paste was decreased than that of SBBC without two foodstuffs. pH of SBBC were rapidly increased to 24 hrs of fermentation and gradually increased thereafter. Total acidity was shown to be reversely decreased as compared to pH tendency. Reducing sugar was increased to 24 hrs of fermentation and then decreased. In SBBC and SBC, potassium was the most abundant followed by phosphorus, magnesium and calcium.

• Korean Journal of Food Science and Technology
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• v.31 no.1
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• pp.196-205
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• 1999

Kochujang prepared by liquid and solid koji using isolated bacteria(Sunchang 1 and Park 2) showing excellent enzyme activities were gamma irradiated at $15{\pm}1.5\;kGy$ to investigate their qualities from the physicochemical, microbiological and enzymatic points of view during fermentaion at $25^{\circ}C$ for 90 days. The amino type nitrogen contents were $0.6{\sim}0.7%$ after 30 days of fermentation. Irradiation completly stopped gas production which is one of biggest problem of kochujang distribution. Enzyme activities were some different according to koji and irradiation treatment. Amino type nitrogen content as one the most important quality indice was higher in kochujang fermented by isolated bacteria (Park 2) than non inoculated traditional kochujang. But sensory quality was not significantly different.

• Food Science of Animal Resources
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• v.33 no.3
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• pp.356-362
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• 2013

We investigated the skin permeability and various biological activities of porcine homogenate of placenta (HP) with the highest protein contents (452.89 ${\mu}g/mg$). The content of protein in subcritical extract of HP (SPE) was decreased from the initial content of 452.9 ${\mu}g/mg$ to 262.7 ${\mu}g/mg$ at 3 h subcritical extract. The contents of amino type nitrogen (A-N) were sharply increased from 35.1 ${\mu}g/mg$ of initial content to 305.9 ${\mu}g/mg$ at 3 h subcritical extract. The HP showed a noticeable activity in terms of antioxidant capacity for ferric reducing antioxidant power (FRAP) assay and especially for 2,2'-Azinobis- (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) method. HP, SPE-0.5, SPE-2 and SPE-3 showed inhibitory effect on elastase activities with an $IC_{50}$ of 46.1, 42.9, 31.6 and 34.7 ${\mu}g/mL$, respectively. SPEs showed more significantly inhibitory effect than HP (p<0.05). The skin permeability of the SPEs was higher than that of the HP. SPE-3 showed highest skin permeation and the permeability was significantly higher than that of HP. SPE-2 also showed significantly higher permeation than HP after 4 h. As expected, increase of extraction time significantly increased skin permeability in the subcritical extract of HP (SPE). From these results, in terms of cost and source availability, porcine placenta extracted with subcritical extraction has advantages over untreated PE and have potential as a cosmetic ingredient.

• The Korean Journal of Food And Nutrition
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• v.35 no.2
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• pp.106-115
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• 2022

The purpose of this study was to examine the quality characteristics of byeolmijang prepared several roasted whole grain powders (oat, brown rice, black soybean, corn) for eight weeks. As the fermentation progressed, the pH decreased from 6.10~6.12 to 4.48~4.92 and the total acidity increased dramatically from 0.41~0.48% to 1.67~2.24%. There were no differences in the moisture content. The content of reducing sugar decreased, in particular, brown rice sample(C) decreased significantly than the other samples during fermentation. In color, L and b-value decreased all samples, whereas a-value showed a tendency to slightly increase. The total cell counts and lactic acid bacteria revealed an increasing tendency during fermentation. In case of the amino-type nitrogen contents, it increased significantly during the fermentation period, especially control sample (A) showed the highest content significantly. The total polyphenol of all samples increased in the fermentation period. ABTS and DPPH radical scavenging activities also increased, especially corn sample (E) had the highest levels. In by electronic tongue analysis, corn sample (E) revealed higher umami and sourness than the control. So, by adding roasted corn powder, it can enhance function and taste of byeolmijang.

• Food Science and Preservation
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• v.12 no.3
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• pp.292-298
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• 2005

Kochujang(Korean red pepper paste) of 600 g was fermented in the different types of vessels (glass, polypropylene(PP), polyethylene terephthalate(PET), stainless steel and Korean porcelain called onggi) with 627 mL of volume during 4 months. The quality changes were monitored for physical, chemical and microbiological attributes. Onggi which had high porosity in the micro-structure provided kochujang with higher microbial counts of aerobic bacteria, lactic acid bacteria and yeasts than those of the other containers. Compared to kochujang fermented in the other containers, kochujang in Onggi showed higher protease activity, amino type nitrogen, and free amino acid content. The kochujang in Onggi also attained higher acidity, lower pH and higher reducing sugar concentration than those in the other containers. All changes were completed 2 or 3 months. Onggi showed water loss and salt increase of the kochujang comparable to those in the other vessels, which was from gradual clogging of the micropores during storage. All physical, chemical and microbiological changes made the kochujang in Onggi attain the sensory quality significantly better than those fermented in the other vessels.

• Korean journal of food and cookery science
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• v.32 no.4
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• pp.400-412
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• 2016

Purpose: This study was conducted to develop easy-made ssamjang products with differentiated materials and methods to meet the needs for a healthy and easy- lifestyle trend with lowered manufacturing expenses. Methods: Ssamjang was made with cheonggukjang and different kinds of jocheong as glutinous (GRSS), sweet potato (SPTSS), sweet pumpkin (SPKSS), bellflower root (BRSS) and ginger (GSS) and stored at $4^{\circ}C$ for 16 weeks. Quality characteristics and consumer acceptability were measured. Results: Titratable acidity was higher in SPTSS and rapidly increased (p<0.05) after 9 weeks in all groups during storage. Amino-type nitrogen contents of SPTSS and SPKSS were the highest and rapidly increased (p<0.05) after 5 weeks. Total free sugar content was higher in GRSS and did not change during storage. Glutamic acid and total free amino acid contents were higher in SPTSS, SPKSS and continuously increased up to 9 weeks. Yeast counts rapidly increased (p<0.05) after 9 weeks reaching 4.0 Log CFU/g in all groups except for SPTSS. Consumer acceptability did not change during storage in all groups and GSS was least preferable. Conclusion: The optimal quality maintenance period of ssamjang with cheonggukjang and jocheong was determined to 7-9 weeks of storage at $4^{\circ}C$ and ginger jocheong was the least preferable materials. We conclude that it is possible to develop easy-made ssamjang products with cheonggukjang and non-fermented materials also skipping aging period.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.1
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• pp.35-43
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• 2016

To evaluate processing suitability of lipoxygenase (LOX)-free genotype soybeans (Jinyang, 05C4 and LS), quality characteristics and antioxidant activities of their Doenjang products were compared to those of Doenjang made from Taekwang soybean (LOX-present) as the control. Moisture and crude protein contents of Doenjang were significantly higher in LS than the control. Crude lipid content was not significantly different and was in the range of 7.92~8.22% in all samples. Carbohydrate content was significantly lower in LS than Taekwang. Content of reducing sugar in Doenjang was significantly higher in Jinyang than Taekwang. Contents of amino-type nitrogen were significantly higher in LOX-free cultivars than Taekwang. Colors of 05C4 and LS Doenjang were not different compared to that of Taekwang, whereas Jinyang Doenjang showed a noticeable color difference. Taekwang Doenjang had a slightly stronger savory taste than another sample. LOX-free cultivars had a strong salty taste. Flavor was the strongest in LS, whereas overall acceptability showed little difference among all samples. The total amino acid content was slightly higher in Jinyang and 05C4 than Taekwang, and content of essential amino acids was higher in Doenjang from LOX-free cultivars than Taekwang. Isoflavon content was significantly higher in Doenjang ($522.16{\sim}684.46{\mu}g/g$) made from LOX-free cultivars than in Taekwang ($374.79{\mu}g/g$). Total phenol content was significantly higher in 05C4 and LS, and flavonoid content was significantly higher in LS than Taekwang. Antioxidant activities were highest in Jinyang based on DPPH radical scavenging and reducing power. ABTS radical scavenging activity was significantly higher in Doenjang made from LOX-free cultivars than Taekwang. These results suggest that Doenjang from LOX-free cultivars could have a suitable genotype for Doenjang processing since it is more effective in terms of amino acids, isoflavone contents, and antioxidant activity.

• Microbiology and Biotechnology Letters
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• v.51 no.1
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• pp.53-58
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• 2023

The glutamic acid producing strain for development savory taste enhancing foods was identified the possibility through application into soybean fermentation. To check the effects on glutamic acid production during soybean fermentation, Lactococcus lactis HY7803 was introduced as a starter. The soybean samples were analyzed on days 0, 7, 14 and 21. The numbers of bacteria decreased gradually, while the content of amino-type nitrogen increased during fermentation in the soybean with L. lactis HY7803. Glutamic acid content in soybeans with L. lactis HY7803 increased from 114.99 ± 9.37 pmol/ul on day 0 to 138.14 ± 1.76 pmol/ul on day 21, showing an overall higher amino acid content than soybeans without L. lactis HY7803 and similar content to soybeans with Aspergillus oryzae SNU-G. It was clearly distinguished through principal component analysis. Consequently, our results indicate that L. lactis HY7803 is available as a fungus replacement and may be a good starter strain for enhancing savory taste in vitro as well as soybean fermentation.