• The Korean Journal of Food And Nutrition
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• v.12 no.5
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• pp.490-495
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• 1999

A thermotolerant yeast Saccharomyces cerevisiae OE-16 was isolated from traditional Meju was investigated on their physiological characteristics and ethanol fermentation ability. Saccharomyces cerevisiae OE-16 were able to grow up to 45$^{\circ}C$ and 40% of glucose. Saccharomyces cerevisiae OE-16 was also resistant to 15% of KCl 1,200ppm of Pb2+, Hg2+ and 500ppm of potassium sorbate. From 20% glucose media Saccharomyces cerevisiae OE-16 produced 83.4g per liter of ethanol at 3$0^{\circ}C$ and 9.5g per liter of ethanol at 4$0^{\circ}C$ for 72 hours.

• Journal of Nutrition and Health
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• v.20 no.2
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• pp.104-110
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• 1987

Thirty mael Sprague Dawley rats of 3 weeks of age were adopted to investigate changes in nutritive quality of the traditional, fermented soybean foods, Meju and Chungkugjang prepared by culturing with Aspergillus oryzae and the rice straw, respectively. The levels of each dietary protein were set at 10% . The effect of supplementation of fermented soybean on the rat diet was evaluated by measuring growth rate, feed efficiency. weight of the pancreas and biological values, such as NPU, PER and NPR on day 10. After incubation of soybean with Aspergilllus oryzae and the rice straw, the contents of crude protein, crude fat and crude ash were increased, but the levels of crude fiber and nitrogen-free extract were reduced. The amounts of feed intake, body weight gain an feed efficiency were greater for the rats fed dietscontaining heated unfermented soybeans or Meju compared to rats fed the diet containing raw soybeans. Pancreating enlargement was observed in the rats fed diets containing raw soybeans. The values of NPR and PER in rats fed diets containing Meju and Chungkugjang were significantly higher than those of rats fed diets containing raw soybeans. The values of NPU in rats fed diets containing raw soybans, heated unfermeted soybeans. Meju and Chungkugjang were 39.40%, 40.60%, 45.00% and 46.205, respectively, demonstrating no significant differences.

• Journal of Microbiology and Biotechnology
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• v.27 no.5
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• pp.916-924
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• 2017

Eighty-five Enterococcus faecalis isolates collected from animals (40 isolates), meju (a Korean fermented soybean product; 27 isolates), humans (10 isolates), and various environmental samples (8 isolates) were subjected to multilocus sequence typing (MLST) to identify genetic differences between samples of different origins. MLST analysis resulted in 44 sequence types (STs), and the eBURST algorithm clustered the STs into 21 clonal complexes (CCs) and 17 singletons. The predominant STs, ST695 (21.1%, 18/85) and ST694 (9.4%, 8/85), were singletons, and only contained isolates originating from meju. None of the STs in the current study belonged to CC2 or CC9, which comprise clinical isolates with high levels of antibiotic resistance. The E. faecalis isolates showed the highest rates of resistance to tetracycline (32.9%), followed by erythromycin (9.4%) and vancomycin (2.4%). All isolates from meju were sensitive to these three antibiotics. Hence, MLST uncovered genetic diversity within E. faecalis, and clustering of the STs using eBURST revealed a correlation between the genotypes and origins of the isolates.

• Microbiology and Biotechnology Letters
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• v.24 no.2
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• pp.247-253
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• 1996

Changes in microorganisms, enzyme activities and major components of two types of Doenjang prepared with spring Meju and autumn Meju and Kochujang were investigated during 4 months of fermentation. The viable cell counts of aerobic bacteria in Doenjang and Kochujang were increased up to 60 days of fermentation, but viable cell counts of anaerobic bacteria did not show remarkable changes during fermentation. Viable cell count of yeast showed a rapid increase up to 15 days of fermentation in Doenjang and 60 days in Kochujang. It was found that $\alpha$-amylase activity of autumn Meju Doenjang and glucoamylase activity of Kochujang were higher than the other. Acidic and neutral protease showed the highest activity during 15-30 days of fermentation. The pH of Doenjang was increased up to pH 7.0 until 60 days of fermentation, but pH of Kochujang gradually decreased during fermentation. Moisture content of spring Meju Doenjang and Kochujang decreased to 40% during ferme- ntation and reducing sugar content of Kochujang increased up to 15 days of fermentation, but decreased after that.

• Korean Journal of Food Science and Technology
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• v.30 no.4
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• pp.908-915
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• 1998

By using Korean native soybean, traditional meju was prepared in Chuncheon, Kangweondo according to the traditional process. Analysis of physico-chemical, enzymatic and microbiological changes during meju fermentation were carried out in order to obtain a basic information for industrial scale production of meju. The enviroments for natural meju fermentation were $10{\sim}15^{\circ}C$ and $60{\sim}70%{\;}RH$. Moisture content decreased from 59% to 11% (exterior section) and 19% (interior section). the pH of meju rapidly increased up to 8.5 at $33^{rd}{\;}day$ of fermentation and thereafter decreased down to 7.9 at $70^{th}{\;}day$ of fermentation. Souble protein content was 1.47% at initial stage and increased up to $6.31{\sim}7.34%$ at $33^{rd}{\;}day$ of fermentation. Amino nitrogen content was $460{\sim}770{\;}mg%$ at $70^{th}{\;}day$ of fermentation. the color of meju became gradually black and decreased in redness and yellowness. During the process, protease and lipase seemed to play an important role in the digestion of soy protein and fat. Acidic protease activity increased up to $135.9{\sim}152.4{\;}unit/g$ at $33^{rd}{\;}day$ of fermentation and were $181.3{\sim}272.6{\;}unit/g$ at $70^{th}{\;}day$ of fermentation. Lipase activity increased up to 6 unit/g (interior section) and 15 unit/g (exterior section) at $70^{th}{\;}day$ of fermentation. the viable cell count of meju was at the level of $10^8{\;}CFU/g$ during the overall fermentation period. Aerobic halophilic count was $1.51{\times}10^7{\;}CFU/g$ at initial stage and maintained $10^8{\;}CFU/g$ level during the process. Initial anaerobic cell count was $2.0^9{\times}10^4{\;}CFU/g$ and increased up to $10^5{\;}CFU/g$ level at 47 days. Yeast and mold counts were $10^4{\sim}10^5{\;}CFU/g$ for the fermentation period.

• Food Science and Preservation
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• v.16 no.2
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• pp.217-222
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• 2009

The objective of this study was to obtain basic data on Korean traditional meju collected in 17 regions of Korea, to define and control meju quality. The moisture, crude fat, crude protein, and amino nitrogen contents of meju were 9.83-36.24%(w/w), 17.46-28.74%(w/w), 42.00-45.54%(w/w), and 223.65-1137.68 mg%, respectively. Meju was the enzyme source which made the soy sauce and doenjang. The $\alpha$-amylase, $\beta$-amylase, and protease levels were 130.32-1254.45, 30.07-167.88 and 72.53-340.04 units, respectively. Regional enzyme activities differed widely. Bacterial levels were $4.8{\times}10^7-2.6{\times}10^{10}cfu/g$, and molds and yeasts were at $4.3{\times}10^4-7.9{\times}10^6cfu/g$.

• 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.

• Journal of Environmental Health Sciences
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• v.30 no.1
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• pp.22-28
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• 2004

This study was performed to investigate the changes of amino nitrogen, total amino acids, free amino acids, and color of Korean traditional soy sauce (kan-jang) during the ripening and storage for 12 months and the characteristics of the changes. All of the preparation methods for soy sauce followed the recommendations of the Korea Food Research Institute. The components of soy sauce were analyzed at 0,6, and 12 months. The contents of amino nitrogen of soy sauce were significantly higher than that of soybeans or meju (soybean cakes) at the initial stage of storage (p<0.05), and decreased during the storage. The content of total amino acids of soybean sauce was significantly lower than that of soybeans, and the content of free amino acids was higher than that of soybeans (p<0.05). The contents of total and free amino acids decreased in soy sauce after 12 months of storage (p<0.05). The composition of total and free amino acids and their ratios of soy sauce were changed during the storage. The ratios of free to total amino acids of soybeans, meju, and soy sauce were 0.8％, 17.3％, and 53.1-59.8％, respectively. Glutamic acid, which represents the savory taste, was detected the most abundantly in soy sauce during the storage. The ratios of free to total amino acids of glutamic acid were 42.9-59.5％ in soy sauce. Lightness of Hunter color of soy sauce decreased over time (p<0.05). This study indicates that the ratios of free to total amino acids of soy sauce were much higher than those of soybeans, although its contents of total amino acids were much lower than those of soybeans. This study also indicates that this comes from the preparation and fermentation of meju. It was suspected that the organoleptic characteristics of soy sauce derived from the amino nitrogen, amino acids, and color might be inferior over 1 year of storage time. However, more detailed research should be conducted to interpretate this characteristics more accurately.

• KSBB Journal
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• v.14 no.4
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• pp.434-439
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• 1999

A wild yeast S-13 which has excellent killer toxin activity to gas-producing yeast of traditional Doenjang and Kochujang was selected among forty seven strains of Meju yeasts and identified as Hansenular capsulata S-13 by investigation of the morphological, cultural and physiological properties. The optimal conditions for the production of killer toxin were investigated. H. capsulata s-13 showed the higest killer toxin activities when it was cultured up to the late-log phase of 36 hr in YEPD medium (pH4.5) at $25^{\circ}C$ H. capsultara S-13 showed killer toxin activities to seven strains of industrial yeasts such as S. cerevisiae, C. veratilis and P. membranaefacieus.

• Korean Journal of Food Science and Technology
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• v.30 no.3
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• pp.608-614
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• 1998

In order to establish the scientific foundations for the production of Korean traditional kanjang (soy sauce) in a semi-pilot scale, meju preparation and kanjang mashing methods were investigated. Two types of meju, one that was prepared by conventional method (CM-meju) and the other that prepared by modified conventional method (MCM-meju), were made and compared their characteristics. The former made of cooked and crushed soybean with a brick shape was fermented at $15{\sim}20^{\circ}C\;and\;40{\sim}50%$ relative humidity (RH) for 30 days in koji room and the latter was fermented at $25{\sim}30^{\circ}C\;and\;80{\sim}90%$ RH seemingly being optimum for the growth of meju-organisms for the same period. The quality of MCM-meju as a raw material for the kanjang preparation was considered to be superior to that of CM-meju as the higher soluble nitrogen and total free amino acids content, the major factor for the evaluation of the quality of meju, were found in the former although the higher total nitrogen content and lower % weight loss were observed in the latter during meju preparation process. The quality of MCM-kanjang with higher total nitrogen, free amino acids, free sugars and the lower residual nitrogen content in cake after separation of kanjang was also found to be superior to that of CM-kanjang in sensory evaluation results.