• Food Science and Preservation
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• v.23 no.6
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• pp.788-796
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• 2016

This study presented the change of quality characteristics of Doenjang with various salt concentrations (4, 8, 15, and 20%) during 12 months. The pHs of Doenjang during fermentation were gradually increased for 12 months, whereas the pHs of Doenjang with 4 and 8% salt increased rapidly. Titratable acidity of Doenjang with 4 and 8% salt was high at initial time, while Doenjang with 15 and 20% salt was high at the 9 and 12 months. The amino-type nitrogen content of Doenjang with 4 and 8% salt was increased and ${\alpha}-amylase$ activity of all Doenjang was decreased during whole fermentation period. The protease activity of Doenjang with 4 and 8% salt was higher than Doenjang with 15 and 20% salt until 7 months. Total aerobic bacteria number 8.0~9.1 log CFU/g for 12 months, which was steady during fermentation period. Doenjang with 8% salt showed the highest score in umami taste whereas the lowest score in bitterness, astringency, and sourness tastes between 5 and 12 months. In conclusion, Doenjang with 8% salt was a suitable concentration for low-salt fermented foods.

• The Korean Journal of Food And Nutrition
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• v.32 no.6
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• pp.651-661
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• 2019

Suaeda asparagoides (Miq.) is a salt marsh plant, long been prescribed in traditional medicine for the treatment of hypertension and liver toxification in Asian countries. The powder of S. asparagoides was added at the ratio of 0, 5, and 10%, respectively, of grain-type Meju to manufacture Doenjang in brine according to the salt concentration (8 and 12%). After 24 weeks of fermentation, the Doenjang samples were determined to have an anti-inflammatory effect on RAW 264.7 cells. Evaluation of the anti-inflammatory effect of Doenjang added S. asparagoides powder extracted using 80% EtOH, was performed to study the inhibition of pro-inflammatory factors such as NF-κB (nuclar factor κB), NO (nitric oxide), TNF-α (tumor necrosis factor alpha), IL-6 (interleukin-6), iNOS (inducible nitric oxide synthase), and COX-2 (cyclooxygenase-2) in lipopolysaccharide (LPS)-induced RAW 264.7 cells. The results showed that the Doenjang extracts reduced the production of NO, IL-6, COX-2, and iNOS increased in the LPS-stimulated RAW cell without cytotoxicity. In the case of the NF-κB and TNF-α there was no significant difference between the control and samples. In conclusion, these results suggest that Doenjang added with the S. asparagoides powder acts as functional fermented food with anti-inflammation effect.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.5
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• pp.775-783
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• 1997

Morphologically different 18 strains were isolated and examined for their abilities to inhibit ACE. Those strains were cultured in the medium containing 10% of soybean extract at 37$^{\circ}C$ for 48hr or fermented with boiled soybean at 3$0^{\circ}C$ for 60 days. The concentration of inhibitors to inhibit 50% of ACE activity, $IC_{50}$ was measured on the culture broth of each strain and also on the hot-water extract from 20, 40 and 60 day fermented Doenjang by each strain. As a result, SCB-3 which is isolated from Meju showed the highest ACE inhibitoryactivity on the cultured broth and 40 day matured Doenjang. Then, $IC_{50}$ of SCB-3 was 0.02 mg/ml and 0.26mg/ml respectively. SCB-3 was identified as a Bacillus subtilis based upon its morphological, biochemical and physiological properties. Changes in general components and ACE inhibitory activity of Doenjang fermented by SCB-3 were examined during 90 days. Total acidity of Doenjang was increased from 1.39% to 1.66% and pH was decreased from 6.02 to 5.79 after 90 days fermentation. Total sugar contents were decreased from 16.4% to 15.1% and reducing sugar contents was also decreased from 2.45% to 1.62%. Total nitrogen contents were nearly not changed, but amino nitrogen contents were drastically increased from 196mg% to 541mg%. The numbers of total microorganism were increased to 1.1$\times$$10^{8}$ cells/g after 45 days. Protease activity was increased to 622.1U/g after 75 days. The highest ACE inhibitory activity was shown in 60 day fermented Doenjang and $IC_{50}$ of the hot-water extract was 0.31mg/ml.

• Journal of Microbiology and Biotechnology
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• v.9 no.4
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• pp.504-508
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• 1999

This report compares the selective cytotoxic effects of Doenjang fermented by various Bacillus strains (Bacillus sp. SS9, SSA3, and PM3) on human liver cell lines with that of conventional Doenjang (DTY, DTG, and DTK) and commercial Doenjang (DCM, DCD, and DCS). To investigate selective cytotoxic effects of Doenjang extracts, the cell density of HepG2 (Hepatocellular carcinoma) and CCL-13 (cells derived from human normal liver) was estimated after addition of the extracts by using a viable cell counting method. The maximum selectivity ratio ($IC_{50}$value against CCL-13/$IC_{50}$ value aganist HepG2) was observed by PM3 (extracts of Doenjang fermented with Bacillus sp. PM3). As for morphological changes shown by the addition of PM3 into HepG2 and CCL-13 cultures, HepG2 was significantly disrupted, however, CCL-13 was not affected. Also, the growth rate of HepG2 was decreased significantly by the addition of PM3. Consequently, PM3 showed a more detrimental effect on HepG2 than that on CCL-13.

• Food Science and Biotechnology
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• v.18 no.5
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• pp.1138-1144
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• 2009

This study was carried out to investigate the cooking properties and lipid oxidation stability during storage at $4{\pm}1^{\circ}C$ when the various levels (5 to 20%) of doenjang (Korean fermented soybean paste) were added to pork patties cooked by pan frying (PF) and convection oven (CO). With increasing the addition of doenjang, cooking properties of pork patties revealed the improved cooking yield, less diameter reduction, and less thickness increase. Also, the shear force, hardness, and chewiness of pork patties were reduced. The PF cooking method showed better cooking properties than CO. Lipid oxidation expressed by the thiobarbituric acid reactive substances (TBARS) values was significantly reduced by the addition of more than 5% doenjang (p<0.05). The TBARS values of cooked pork patties by PF were significantly lower than CO during the 8 days of the storage (p<0.05). The development of warmed-over flavor (WOF) in cooked pork patties was delayed as the amount of the doenjang was increased. It was suggested that the addition of doenjang and PF favorably affected the cooking properties and stability of lipid oxidation in pork patties.

• Microbiology and Biotechnology Letters
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• v.44 no.3
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• pp.303-310
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• 2016

In this study, doenjang samples were prepared with different types of salts (12%, w/w): purified salt (PS), 3-year aged solar salt (SS3), 1-year aged solar salt (SS1), and bamboo salt melted 3 times (BS). Whole-soybean mejus were fermented with starters consisting of 2 Bacillus strains, a yeast, and a fungus (starter doenjang), and control mejus were fermented with organisms present naturally in rice straw (non-starter doenjang). The whole-soybean mejus were dried, and then mixed with cooked soybeans and the respective salts. The doenjang samples were fermented for 13 weeks at 25℃. The protease (acid, neutral, and alkaline) activities, fibrinolytic activities, and antioxidant capacities of the samples were examined every week. BS doenjang showed the highest acid protease (6.46 ± 0.20 unit/g) and fibrinolytic activities (0.61 unit/ml). Among the starter doenjang samples, those made with SS and BS showed the highest total phenolic contents after 91 days of fermentation. For antioxidant activities, SS3 doenjang showed higher activities than the other doenjang samples, as evaluated by ABTS, DPPH, and FRAP assays. These results suggest that solar salt, especially aged for 3 years, is better than purified salt in terms of producing better functionalities of doenjang.

• Korean Journal of Food Science and Technology
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• v.45 no.5
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• pp.565-570
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• 2013

This study investigated the detection of naturally occurring preservatives in fermented soybean products. Benzoic acid was identified in all of the analyzed samples (gochujang, ganjang, doenjang, and cheonggugjang). The amounts of benzoic acid were in the range of 0.85-11.69 ppm in gochujang, 1.13-7.95 ppm in ganjang, 0.74-17.77 ppm in doenjang, and 1.03-7.64 ppm in cheonggugjang. Propionic acid was found in 24 of 29 gochujang samples, 21 of 30 ganjang samples, 31 of 33 doenjang samples, and 28 of 30 cheonggugjang samples. The amounts of propionic acid ranged from N.D. (not detected) to 49.29 ppm in gochujang, N.D. to 144.67 ppm in ganjang, N.D. to 309.14 ppm in doenjang, and N.D. to 113.07 ppm in cheonggugjang. Among the fermented soybean products, doenjang had the highest average benzoic acid content whereas cheonggugjang had the highest average propionic acid content.

• Food Science and Industry
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• v.49 no.2
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• pp.34-44
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• 2016

Given that fermented foods, such as kimchi and doenjang, are main food sources for high sodium intake in Korea, there have been needs to develop sodium-reduced kimchi and doenjang with the proper quality. However, small and medium sized business could not actively develop the sodium-reduced products due to lack of techniques and information as well as economical reasons. The most important aspects is to address food safety issues including microbial contaminations in sodium-reduced foods. Hurdle Technology, physical, biological, chemical control technique, would have to be preferentially considered to increase the hygiene safety standards in entire processing steps including raw materials, process water, manufacturing environments, and so on. Once the food hygiene level is stable, the next challenges are to improve the taste of the sodium reduced-products as well as to packaging and storage technologies. The development of a variety of sodium-reduced fermented foods would result in significant mitigation of sodium intake by Korean. This report provides the directions to develop sodium-reduced kimchi, doenjang or pickled food products for small and medium sized business, based on the technical consulting results of sodium reduction project supported by Ministry of Food and Drug Safety in 2015.

• Preventive Nutrition and Food Science
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• v.14 no.2
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• pp.134-141
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• 2009

The changes in components and biological activities of doenjang samples prepared with black soybeans and fermented with Bacillus subtilis SCB were investigated. The amino nitrogen (A-N) contents of samples increased with increasing black soybean content. A doenjang product made using a 1:1 ratio of soybeans-black soybeans showed a maximum level of genistein and daidzein isoflavones ($1111.6{\mu}g/g$) at 110 days of fermentation, along with decreasing contents of genistin and daidzin due to the conversion to aglycones. The black soybean-only doenjang sample showed higher protease activity, including caseinolytic and fibrinolytic enzyme activities, than the other samples, and had relatively higher polyphenol content and DPPH radical scavenging activity. Therefore, doenjang made with additions of black soybeans and fermented by B. subtilis SCB may have improved physiological properties, suggesting this to be a valuable method of preparation.

• Journal of Microbiology and Biotechnology
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• v.26 no.9
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• pp.1533-1541
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• 2016

Samples of doenjang (a fermented soybean paste) were prepared with different types of salts; purified salt (PS), 3-year-aged solar salt (SS3), 1-year-aged solar salt (SS1), and bamboo salt (BS, 3^rd processing product). For starter doenjang samples, selected starters comprising two bacilli, one yeast, and one fungus were inoculated, whereas for non-starter doenjang samples, microorganisms present in rice straw were inoculated after enrichment. The doenjang samples were fermented for 13 weeks at 25℃. During the fermentation period, SS and BS doenjang samples showed higher bacilli counts as well as much lower yeast counts than PS doenjang. At 13 weeks, yeast counts of starter doenjang samples were 7.75, 5.69, 6.08, and 4.74 log CFU/g for PS, SS3, SS1, and BS doenjang, respectively. For non-starter doenjang samples, counts were 7.17, 5.05, 5.92, and 4.54 log CFU/g for PS, SS3, SS1, and BS doenjang, respectively. SS and BS promoted growth of bacilli but inhibited growth of yeasts compared with PS. Debaryomyces hansenii was the dominant yeast in PS doenjang, whereas Candida guilliermondii and Pichia sorbitophila were dominant in SS and BS doenjang. In the sensory evaluation, SS and BS doenjang scored better than PS doenjang. In conclusion, SS and BS seem better than PS for production of high-quality doenjang.