• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.5
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• pp.1010-1016
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• 1999

Protease related mold was isolated and selected as a starter culture for commercial production of meju. Isolated microorganism was identified as Syncephalastrum racemosum PDA 132 2. To obtain basic data about protease for production of soybean peptides and application of the strain in meju fermentation, we extrated and purified protease and charateristics of the enzyme were investigated. The optimum condition for the production of enzyme was pH 4.0, 30oC, 5 days. The protease was purified 19.7 folds by gel filtration and ion exchange chromatography and specific activity was 12.4unit/mg. The purified enzyme was 34kDa in size, thiol protease(100% inhibited by PCMB), and was acidic protease(stable between pH 2.0~5.0). Vmax of the enzyme was 2.14 g/min which was lower(1/50) than that of by Asp. wentti and B. subtilis.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.12
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• pp.1854-1859
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• 2010

Three kinds of Korean traditional Meju were selected and the counts of microorganisms in these Meju were determined. The counts of total aerobic bacteria, lactic acid bacteria and yeasts and molds were 107~108, 106~108 and 107~108 cfu/g, respectively in three Meju and lactic acid bacteria were important microorganisms in the fermentation of Meju. Therefore, we isolated three kinds of dominant lactic acid bacteria from these Meju. They were identified as Leuconostoc mesenteroides (98%, Lm-SMm), Lactobacillus plantarum (99%, Lp-SMm) and Lactococcus lactis (98%, Ll-GAm). Then, enzyme activities and physiological functionalities of three lactic acid bacteria were investigated. Protease, lipase and $\alpha$-amylase activities were detected in three lactic acid bacteria, Ll-GAm showed relatively higher activities than other two lactic acid bacteria. Lm-SMm, Lp-SMm and Ll-GAm showed 45, 48 and 60% of antioxidative activity to 1,1-diphenyl-2-picryhydrazyl (DPPH), and exhibited 45, 67 and 70% of inhibitory effects in HT-29 human colon cancer cells, respectively. These results indicate that three lactic acid bacteria isolated from traditional Meju, especially Ll-GAm are applicable to Meju preparation for soybean paste industry.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.6
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• pp.917-924
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• 1995

Four types of soybean paste(Doenjang), prepared with traditional Korean meju, natto meju, koji and mixture of koji and natto meju, were analyzed for compositions of free sugars and fatty acids. Crude protein content of the soybean pastes were ranged from 10.3~14.6% and in the order of traditional Korean soybena paste>natto soybena paste>koji & natto soybean paste>koji soybean paste during fermentation of Doenjang. Ethyl alcohol contnet was relatively higher in koji and natto soybean paste after fermentation for 75 days, and its content was the highest in koji soybean paste as 2.8% after fermenting for 90 days. Contents of total sugars and reducing sugars decreased during fermentation of doenjang in the order of koji soybena paste>koji and natto soybean paste>traditional soybean paste>natto soybean paste. Among the free sugars glucose, galactose, mannose and arabinose were identified in soybean paste, and glucose and galactose were more bundant. Contents of glucose and total free sugars were the highest in the traditional Korean soybean paste and galactose content was highest in koji soybean paste. In fatty acid compositions of soybean pastes, palmitic, stearic, oleic, linoleic, linolenic and arachidonic acids were analyzed, and the most abundant fatty acid was found to be oleic acid as 38.5~46.9% in all samples tested. But no significant differences in ratio of fatty acid compositions was observed from tested samples during the fermentation period.

• Korean Journal of Food Science and Technology
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• v.33 no.2
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• pp.256-263
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• 2001

Physicochemical characteristics of kochujang prepared with meju, koji and mixture of meju and koji were analyzed during fermentation in order to improve quality of traditional sikhe kochujang. Amino nitrogen content, an index of kochujang quality, was remarkably higher in kochujang prepared with p-2 koji, p-1 koji, mixture of p-2 koji and meju. Titratible acidity of kochujang slightly increased and pH of kochujang increased until 40 days of fermentation and then decreased there after. Citric acid was found as a major organic acid followed in decreasing order by malic, oxalic, succinic, acetic and lactic acids. As a free sugar, maltose, glucose and fructose were detected. Free sugar content was higher in kochujang prepared with p-1 koji than the others. The major free amino acids were aspartic acid, glutamic acid, alanine, phenylalanine and arginine, and total free amino acid content was higher in kochujang prepared with koji, and mixture of meju and koji than the one with traditional meju only. In sensory evaluation, all tested groups did not show a significant difference. This result indicates that addition of koji to sikhe kochujang influences on taste components like free sugars and free amino acids, but decisively not on the sensory properties.

• Preventive Nutrition and Food Science
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• v.16 no.2
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• pp.165-173
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• 2011

Five types of meju were prepared from 100% defatted soybean (DFSG0), a mixture of 90% DFS and 10% glasswort (DFSG1), a mixture of 80% DFS and 20% glasswort (DFSG2), a mixture of 70% DFS and 30% glasswort (DFSG3), and a mixture of 60% DFS and 40% glasswort (DFSG4). Five types of kanjang were separately prepared from the 5 types of meju by ripening in brine for 6 months. The contents of certain minerals (Mg, Ca, Fe, Mn, and Zn), organic acids (citric acid, malic acid) and the antioxidative effects in the kanjang were increased in proportion to the glasswort content in the meju. However, the free amino acid contents in the kanjang were reduced in proportion to the glasswort content in the meju. DFSG1- and DFSG2-kanjang did not show distinct differences from DFSG0-kanjang based on aroma, flavor, and taste that were compared simply by panel tests. The bacterial and fungal community in the fermented meju and kanjang was not affected by the addition of glasswort to the meju-making process. Bacteria belonging to the Lactobacillus and Bacillus genera and the Lactobacillus family predominated, and yeasts belonging to the Saccharomyces genus and fungi belonging to the Aspergillus genus predominated in the fermented meju and kanjang. In conclusion, the glasswort was a supplement that nutritionally improved the kanjang (except for free amino acid contents) but didn't influence the growth of microorganisms that are responsible for the fermentation of meju and kanjang.

• Korean Journal of Food Science and Technology
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• v.3 no.1
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• pp.64-67
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• 1971

The Manufacturing conditions of Chungkukjang were investigated by the use of the soy beans, salt (NaCl) and Bacillus subtilis S.P. In the studies of Chungkukjang Meju protease activity, total acid, free amino nitrogen, optimum times of fermentation and the maturity of Meju were shown the reasonable conditions each at 54 hrs, 24 hrs, between 36 to 42 hrs, between 36 to 42 hrs and at 5 days from the beginning of fermentation. In the studies on the Chungkukjang (Sauce made by meju) the increased amount of free amino nitrogen and total acid were proportional to the increased contents of moisture. The amount of the acid was increased rapidly for 20 day from the beginning and after it slowly. The appropriate content of moisture was 55% in the manufacturing of Chungkukjang.

• The Korean Journal of Mycology
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• v.24 no.4 s.79
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• pp.329-336
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• 1996

From five years' previous work, the fungal isolates of Scopulariopsis were reported to be important flora at the late stage of meju fermentation. Mainly, the white or pale brown powders of spore mass of these fungi were observed on the surfaces of rectangular mejus, and to be an important sign for well-done Korean traditional home - made mejus. Out of the five isolates previously collected and stored, two kinds of Scopulariopsis isolates were identified as S. brevicauli and S. fusca. The microscopic differences between two were found to be branching patterns of annellophore and ornamentations of spore wall (warty and smooth). However, the intermediate form between two ornamentations of spore wall were also observed in our isolates. This observation was consistent with other result made from the protein electrophoresis. The isolates of Scopulariopsis were considered to be similar or superior to those of Aspergillus species, as compared with production of protease and amylase related enzymes. Thus, these isolates were speculated to be important fungi in Korean traditional home - made meju fermentation and also in production of protease and amylase.

• Journal of Microbiology and Biotechnology
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• v.24 no.3
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• pp.334-336
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• 2014

A new species named Aspergillus cumulatus sp. nov. is described in Aspergillus section Aspergillus (Eurotium state). The type strain (KACC $47316^T$) of this species was isolated from rice straw used in meju fermentations in Korea, and other strains were isolated from the air in a meju fermentation room. The species is characterized by growth at a wide range of water activities and the formation of aerial hyphae on malt extract 60% sucrose agar (ME60S) that resemble a cumulus cloud. Furthermore, A. cumulatus produces yellow ascomata containing small lenticular ascospores (5.1-5.7 ${\mu}m$) with a wide furrow, low equatorial crests, and tuberculate convex surface. The species is phylogenetically distinct from the other reported Aspergillus section Aspergillus species based on multilocus sequence typing using rDNA-ITS, ${\beta}$-tubulin, calmodulin, and RNA polymerase II genes.

• Food Science and Preservation
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• v.8 no.4
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• pp.405-411
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• 2001

This study was conducted to investigate the effect of rice powder m tile enzyme (protease, $\alpha$-amylase, $\beta$-amylase and glucoamylase) activities of soybean meju fermented by Monascus prepureus and Monascus pilosus. The activities of the enzyme in the rice meju and the soybean meju fermented by M. pilosus were higher than those by M. perpureus. Protease activity of powdered rice meju was higher than that of granular rice meju, while $\alpha$-amylase, $\beta$-amylase and glucoamylase activities were higher in granular rice meju. Protease activity in soybean meju fermented by adding of the cultured medium of Monascus strains(CMM) as a seed inocula were higher than those of the rice powder meju, while $\alpha$-amyulase, $\beta$-amylase and glucoamylase activiities were lower than those of soybean meju by CMM. The concentration of rice powder to show maximum protease activity in soybean meju was also 10% against steamed soybean. But $\alpha$-amylase activity of soybean medju by the CMM added 2% powdered rice showed lower but the activity increaed with an increase in powdered rice, whereas $\beta$-amylase and glucoamylase activiities decreased with an increase in powdered rice. Protease activity of soybean meju fermented by 10% rice meju fermented by M. pilo년 as a seed inocula was higher than that of the meju fermented by Aspergillus oryzae, whereas $\beta$-amylase and glucoamylase activities of the soybean meju showed less than 50%.

• Korean Journal of Food Science and Technology
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• v.33 no.1
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• pp.94-99
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• 2001

Kochujangs(fermented hot pepper-soybean paste) were prepared either using traditional meju (koji for kochujang) or controlled meju fermented by pure isolates (P-1, P-2), which were screened from traditional meju collected at Sunchang area. The isolates were characterized for their superiority on amylase and protease activities, and overall flavor of the culture on cooked soybean. Bacterial cell counts were not different in all treatments of kochujang during fermentation. The mold counts of each treatment dropped to undetectable level after 40 and 60 days of fermentation, respectively. Heat treatment($60^{\circ}C$, 15 min) before fermentation stopped gas formation and had no effect on bacterial cell count, but the growth of yeast was depressed. Total accumulative volume of gas produced during kochujang fermentation was depended on load of yeast in kochujang and the kochujang using P-2 koji produced least amount of gas among all treatments. The amylase and protease activities of kochujang were not significantly different among traditional and controlled kochujangs.