• Food Science of Animal Resources
• /
• v.24 no.4
• /
• pp.405-410
• /
• 2004

This study was performed to investigate the antioxidative activity of soybean products extracts using 1, 1-diphenyl-2-picrylhydrazyl (DPPH) and thiobarbituric acid (TBA) method for application of animal products. All three extracts (natto, soybean paste, soybean milk extract) were found to have an ability to donate hydrogen to DPPH. Especially, natto and soybean paste extract were more effective than that of soybean milk on the antioxidative activities. Natto and soybean paste extract were stronger than butylhydroxy toluene (BHT), butyl hydroxyl anisole (BHA) (5${\times}$10$^{-4}$ M) and ascorbic acid (5.7${\times}$10$^{-3}$ M) previously well known as antioxidants. These extracts also showed a synergistic effect. TBA values of natto (45.8％) and soybean paste extract (45.2％) were stronger than that of soybean milk extract (33.6％). These results suggest that soybean product extracts have antioxidative activities and synergistic effects.

• Microbiology and Biotechnology Letters
• /
• v.34 no.4
• /
• pp.299-305
• /
• 2006

In this study, we have isolated and identified a proteolytic bacterium from conventional Cheongkukjang. We also characterized several bioactivity of Cheongkukjang, which was fermented by an isolated strain. One strain out of about $10^4$ strains obtained from Cheongkukjang showed relatively high proteolytic activity was selected and named as a Bacillus subtilis LSH805 strain. White soy-bean Cheongkukjang possessed less odor and more viscous substance than black soy-bean Cheongkukjang. Cheongkukjang showed fibrinolytic activity, and about 1,500 mg fibrin was degraded after 20 h incubation. Although nitric oxide (NO) assays of soy-bean and Cheongkukjang were almost the same, their activities were significantly higher than that of no treatment. Activity of water fraction of Cheongkukjang was somewhat higher than that of soy-bean. Fibrinolytic and NO assays of Cheongkukjang suggest that Cheongkukjang, which was fermented by an isolated strain may be a useful candidate for natural fibrinolytic and macrophage-stimulating agents.

• Food Science and Preservation
• /
• v.24 no.8
• /
• pp.1168-1179
• /
• 2017

In this study, we tried to screen the Bacillus strain having safety probability by isolation of strains from traditional fermented food, measurement of probiotic properties, and the fermentative characteristics of Cheonggukjang. We isolated 400 Bacillus-like isolates from traditional fermented foods. Selected strains examined on the prevalent characteristic such as extracellular enzyme and antibacterial activities, and their safety probability was confirmed by biogenic amine productivity, hemolytic, and harmful substances and enzyme productivity. We selected the 5 strains by analysis of biogenic amine, antibacterial and B. cereus toxic associated gene. Five selected strains were examined on cell surface hydrophobicity, and bile and acid tolerance, and we selected the SRCM100730 as the final strain. SRCM100730 was confirmed B. amyloliquefaciens by 16S rRNA sequencing, and named the B. amyloloquefaciens SRCM100730 (KCCM11966P). Finally, we manufactured Cheonggukjang using SRCM100730 for confirmation of fermentation properties. Manufactured Cheonggukjang did not contain B. cereus, and showed that ${\gamma}$-PGA and extracellular enzyme activities were superior to commercial Chunggukjang. Amino nitrogen content was 544.02 mg% and 26 free amino acid were detected, and the bitterness-related amino acid content was lower than commercial Cheonggukjang. Especially, the amount of GABA was 3 fold higher than commercial Cheonggukjang. These results suggest that SRCM100730 have high availability in commercial probiotics market and fermented food industry.

• Korean Journal of Food Science and Technology
• /
• v.26 no.3
• /
• pp.250-254
• /
• 1994

The quality characteristics of freeze-dried Chungkook-jang soup, stored at $25^{\circ}C$, $35^{\circ}C$ and $45^{\circ}C$ was investigated. Peroxide value(POV) was increased as the storage time was extended. Browning reaction occured earlier in the sample stored at $45^{\circ}C$ than those stored at $35^{\circ}C$ and $25^{\circ}C$. Red color developed more intensely in the sample stored at $45^{\circ}C$. However, moisture content was not changed during storage. Regression analyses between sensory scores and quality characteristics showed that the peroxide formation of oil contained in Chungkook-jang soup was the major quality index for the deterioration of Chungkoak-jang soup.

• Proceedings of the Korean Society of Food and Cookery Science Conference
• /
• 2001.06a
• /
• pp.298-308
• /
• 2001

장류는 콩을 주재료로 하는 우리 나라의 전통적인 발효식품으로서 중요한 조미료로 사용되고 있다. 장의 종류는 우리 고유의 전통식 제법에 의한 재래형과 일본식 또는 중국식 제법에 의한 외래형으로 나눌 수 있는데 간장, 된장, 청국장, 고추장 등이 포함된다. 또한 가정에서 담그는 장류와 산업체에서 다량 제조하는 것으로 나눌 수 있다. 장류는 그 원료, 지방의 기후, 환경 등 기타 요인에 의해 변화를 보이며 제조법이 차이가 나는데 맛은 메주에 의해 좌우된다 우리 나라에서 장류가 산업적으로 생산하기 시작한 것은 일본인의 정치 침투와 더불어 시작되었으며, 해방이후 국군이 창설되면서 수요가 갑자기 증가하였다. 또한 서구화의 영향으로 사회구조가 바뀌고 인구의 도시집중화, 주택구조 변화와 자가 제조 등의 어려움으로 공장제품에 대한 수요가 따라서 증가하였다. 최근에는 장류는 조미료로서의 역할 이외에 영양 강화나 생리활성물질을 함유한 식품으로서 그 가치를 찾을 수 있다. 우선 장류가 어떻게 발전되어 왔으며, 가정에서 담가먹지 않고 시판 중인 제품을 구입하는 경우 어떤 종류의 장이 판매되고 있으며 어느 산업체에서 생산되고 있는지 알아본다. 현재 장류를 상품화하고 또 편의식품화 하려고 할 때 문제점과 장류 산업이 나아가야 할 방향에 대해 소개하고자 한다.

• Journal of the Korean Society of Food Culture
• /
• v.13 no.1
• /
• pp.59-64
• /
• 1998

In order to find causes of the difference in taste between Korean and Japanese soybean paste, comparian was made on the free amino acids composition in soybean paste in those two countries. It was found that the free amino acid composition of commercial soybean paste made in Korea was analogous to homemade soybean paste, and the commercial soybean paste made in Japan, was analogous to homemade soybean paste. And there was a similarity on the point that the glutamic acid content was the highest of all free amino acids content in both Korean and Japanese soybean pastes. There was a difference in the mean total free amino acids content between Korean and Japanese soybean paste. The mean ratio of the glutamic acid content to total free amino acid content in Korean and Japanese soybean paste was on the range of $11.5%{\sim}22.6%$ and $10.4%{\sim}12.5%$, respectively. These results suggest that glutamic acid determines taste in Korean and Japanese soybean paste.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.36 no.1
• /
• pp.65-71
• /
• 2007

Five different commercial chungkukjang powders (A$\sim$E) were compared based on their physicochemical, organoleptic and functional properties. The proximate composition of the five samples ranged from 6.07 to 8.54% in moisture, 15.31 to 27.07% in crude protein, 20.19 to 24.75% in crude lipid, 34.84 to 52.41% in carbohydrate, and 3.69 to 5.26% in ash. The pH of the samples ranged from 5.58 to 6.11, and Hunter's colors showed 70.01$\sim$77.22 for L value, 0.91$\sim$4.64 for a value and 23.72$\sim$31.00 for b value depending on the product. The microbial counts were 8.16$\sim$g.60 log CFU/g for aerobic bacteria, $\sim$4.16 log CFU/g for yeasts & molds, and 1.07$\sim$3.88 log CFU/g for coliforms. The contents of reducing sugars and amino-N were 1.89$\sim$2.41% and 2.83$\sim$7.31%, respectively. Free amino acids were mainly composed of glutamic acid, valine, leucine, phenylalanine, and lysine. The amounts of total phenolics and total flavonoids were 108$\sim$302 mg% and 2.73$\sim$9.41, respectively, with some variations in the products. However, the isoflavone contents, which were composed of genistein (63.26$\sim$217.16${\mu}g/g$), daidzein (58.24$\sim$166.65${\mu}g/g$), genistin (2.66$\sim$55.68${\mu}g/g$), and glycitein (12.26$\sim$17.82${\mu}g/g$), were apparently different per product. The sensory scores for color, smell, taste and overall preference for the five chungkukjang products, which were evaluated by panels in their 20's and 30's using 7-point scoring test, ranged from 3.20 to 4.05.

• Korean Journal of Food Science and Technology
• /
• v.38 no.4
• /
• pp.475-482
• /
• 2006

The quality characteristics and functional properties of fermented soybean by lactic acid bacteria (FSB) were investigated and compared with those of soybean (control) and commercial cheonggukjang Powder (CGP). The crude protein, lipid, and fiber contents of FSB were similar to those in CGP. The vitamin $B_2$ content in FSB (1.4 mg%) was similar to the control (1.3 mg%) whereas it was remarkably low in the CGP (0.2 mg%). The bright yellow color of FSB determined by Hunter's colormeter was quite different from the dark reddish brown color of the CGP. The pH of FSB was the lowest and thee amino-nitrogen was 517.2 mg%, which was higher than that in CGP (468.1 mg%). Glutamic acid, aspartic acid and leucine were the most abundant amino acids. In particular, the increase in the glutamic acid level was noticeable in FSB. The fatty acid compositions of FSB and CGP were similar to the control. However, the sucrose and fructose levels were lower after fermentation but the glucose level was higher. The results of isoflavone analysis by HPLC showed that the levels of daidzein and genistein in FSB were as much as 48.33 and 52.82 mg%, respectively, which is higher than that found in CGP. The DPPH free radical scavenging effects of FSB and CGP were 1.8 times higher an those of the control. The fibrinolytic activity determined by the diameter of the lysed area on the fibrin plate was the most effective in FSB. In conclusion, it is believed that FSB has a similar or higher quality than CGP. Therefore, FSB is expected to be good functional food material.

• Korean Journal of Food Science and Technology
• /
• v.39 no.5
• /
• pp.541-545
• /
• 2007

The potential to produce biogenic amines was investigated in microbial strains isolated from fermented soybean paste, cheonggukjang. The typical levels of 11 biogenic amines, including putrescine, histamine, and tryptamine, were analyzed in commercial cheonggukjang. The tyramine and histamine levels in the samples ranged from 4.2 to 483.1 mg $kg^{-1}$ and 0.2 to $70.3mg\;kg^{-l}$, respectively. A total of 4 microbial strains of Bacillus sp. were isolated from cheonggukjang. The Bacillus sp. were identified as B. amyloliquefaciens, B. subtilis, and B. licheniformis based on phenotypic characteristics, which included using the VITEK system. The screening plate method for detecting amino acid decarboxylase positive microorganisms was performed. The results fer amino decarboxylation were positive, and biogenic amine formation was evaluated by the confirmation of amine-forming capacity.

• Korean Journal of Food Science and Technology
• /
• v.34 no.1
• /
• pp.79-84
• /
• 2002

Changes of microbiological and physicochemical characteristics of gamma irradiated Doenjang with low salt were studied. Samples were prepared by mixing the Doenjang and the Chungkukjang with 6% and 8% of salinity. The mixture was irradiated by gamma-ray with dose of 0, 5, 10, 20 kGy, and each sample was stored at $25^{\circ}C$ for 8 weeks. The results showed that the Bacillus cell was inactivated by $10^4-10^5\;cells/g$ with dose of 10 kGy, and yeast and Lactobacillus group were nearly eliminated by 10 kGy. The general quality of gamma irradiated low salt Doenjang, such as amino nitrogen, protease activity, and pH, were more stable than that of control during storage periods. The sensory evaluations showed that 8% (salt)-5 kGy and 6% (salt)-10 kGy irradiated samples were more acceptable than market purchased Doenjang. Therefore, it was considered that gamma irradiation was effective for maintaining better quality of low salt Doenjang and suitable radiation dose was 5 kGy in 8% salted, and 10 kGy in 6% salted sample.