• Journal of Food Hygiene and Safety
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• v.19 no.1
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• pp.31-37
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• 2004

This study was performed to investigate the changes of amino nitrogen, total amino acids, free amino acids, and cole. of traditional Korean soybean paste (doen-jang) during the ripening and storage for 12 months. All of the preparation methods for soybean paste followed the recommendations of the Korea Food Research Institute. The components of soybean paste were analyzed at 0, 6, and 12 months. The content of amino nitrogen of soybean paste was 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 composition of total and free amino acids and their ratios of soybean paste were changed during the storage. The ratios of free to total amino acids of soybeans, meju, and soybean paste were 0.8%, 17.3%, and 20.4∼32.9%, respectively. Glutamic acid, which represents the savory taste, was detected the most abundantly in soybean paste during the storage. The ratios of free to total amino acids of glutamic acid were 21.1∼41.5% in soybean paste. Lightness, redness and yellowness of Hunter color of soybean paste decreased over time (p〈0.05). The results of this study indicate that the ratios of fee to total amino acids of soybean paste were much higher than those of soybeans, although its contents of total amino acids were much lower than those of soybeans. The results also indicate that this comes from the preparation and fermentation of meju. It was suspected that the organoleptic quality of soybean paste derived from these three components might be inferior over 1 year of storage time.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.2
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• pp.314-318
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• 1997

This study was performed to examine the effects of Meju supplementation to high cholesterol diet on lipid metabolism in rats. Male Sprague-Dawley rats were divided into two groups(Steamed soybean, Meju) and were fed with 0.5% cholesterol diet. Serum and liver lipid profiles and fecal bile acids excretion were examined after four weeks of experimental diet. Food intake, weight gain and liver weight were not significantly different between the two groups. Total cholesterol concentrations in serum was significantly lower in Meju group compared to steamed soybean group(p＜0.05). HDL-cholesterol, triglyceride, phospholipids and nonestrified fatty acid concentrations in serum were not significantly different between the two groups. Cholesterol, triglyceride, and phospholipids concentrations in liver were not significantly different between the two groups. Fecal bile acid excretion were markedly higher in Meju groups than the group fed steamed soybean(p＜0.05). These results suggest that the cholesterol lowering effect by Meju supplementation might be resulted from the modulation of fecal bile acid excretion in rats.

• Applied Biological Chemistry
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• v.42 no.4
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• pp.277-282
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• 1999

This study was carried out to clarify the microorganisms which participated in the fermentation of kanjang. The changes in the viable cell counts of total aerobic bacteria, lactic acid bacteria and yeasts for raw soybean, soybean during cooking, meju during cultivation, and kanjang mash during maturing were investigated along with the changes in components during those periods. Lactic acid bacteria that were found to be $6{\times}10^2\;CFU/g$ in raw soybean were disappeared after cooking process, but total aerobic bacteria were diminished from $1.9{\times}10^6\;CFU/g$ to $10^2\;CFU/g$. Aerobic bacteria of inner and outer parts of meju increased to more than $10^9\;CFU/g$. The higher viable cell counts of lactic acid bacteria in the inner parts of meju were observed than those in outer ones. On the contrary, significantly higher viable cell counts of yeasts in the outer parts of meju were found. Total nitrogen content and color density of kanjang increased by using meju with extended cultivation periods. No significant differences were observed in microbial counts between kanjang mash with aeration and non-aeration during kanajng mash maturing.

• The Korean Journal of Food And Nutrition
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• v.13 no.1
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• pp.28-35
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• 2000

As a result of survey of one hundred grain weight and been husk/whole bean ratio of 25 soybean varieties, the one was ranged 12.1∼27.1g and Saeal was highest as 27.1g, and Kwangan was lowest as 12.1g, while the other was revealed that Sinpladal 2 was highest as 9.40%, and Jangyebo was lowest, as 6.13%. Contents of crude protein were ranged 38∼48.5% which Tanback was highest as 48.5%, and Jangyeob was lowest as 39%. Crude lipid contained 17∼22%, and Muhan was highest as 48.5% and Tanback was lowest as 39%. Range of water uptake ratio and hardness after soaking were 235.9∼202.8% and 0.890∼2.593kg/3.14$\textrm{mm}^2$ and Jinpum was highest as 2.593kg/3.14$\textrm{mm}^2$, while Tanwon was lowest as 0.066kg/3.14$\textrm{mm}^2$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.3
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• pp.383-389
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• 1997

Doenjang(fermented soybean paste) was prepared by the series of processes including soaking, cooking, first fermentation(3 days at 30$\pm$2$^{\circ}C$) for the preparation of meju(soybean koji) after inoclulation of Aspergillus oryzae, and further fermentation (60 days at 30$\pm$2$^{\circ}C$) for the ripening after addition of salt 13% to meju. the crude phenolics extracted from defatted soybean and doenjang were fractionated onto the neutral phenolics(isofavonoids) and acidic phenolics(phenolic acids), respectively. Composition and antioxidative characteristics of phenolic fractions were determined. The neutral phenolic fractions contained genistin, genistein and daidzein; on the other hand, acidic phenolic fractions had syringic acid and seven other components. The content of genistin in doenjang dramatically decreased at the early stage of fermentation, whereas the content of genistein rather increased. In addition, the content of syringic acid of acidic phenolic fractions were increased during fermentation. These changes in individual phenolic components affected the antioxidative activity of neutral phenolics or acidic phenolics. antioxidative activity of phenolic compounds were evaluated during soybean fermentation. The antioxidative and free radical scavenging activity of neutral phenolic fractions and acidic phenolic fractions on linoleic acid autoxidation were also investigated.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.3
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• pp.376-382
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• 1997

Antioxidative characteristics of doenjang(fermented soybeans paste) phenolics on the lipid oxidation systems were studied by the determination of the oxidative related activity including lipoxygenase (LOX) inhibition, metal chelating and free radical scavengning of doenjang phenolics. Manlikong variety containing the highest amounts of phenolic compounds among the soybean variety, was used for doenjang processing. Doenjang was prepared by the series of processes including soaking for overnight, cooking for 1hr at 12Lb, first fermentation (3 days at 30$\pm$2$^{\circ}C$) for the preparation of meju(soybean koji) after inoculation of Asp. oryzae, and further fermentation(60 days at 30$\pm$2$^{\circ}C$) for the ripening after addition of salt 13% to meju. In order to investigate the antioxidative activity of phenolics in doenjang, the doenjang phenolics was extracted with methanol form freeze dried defatted doenjang. Antioxidative effects of methanol extract on linoleic acid oxidation system were observed by the significantly decreased levels of peroxide and conjugated diene formation. In addition, methanol extract resulted in the inhibition of LOX activity. and also, metal(FeCl$_3$) chelation and free radical scavengning activities were increased with increasing concentration of methanol extract.

• Korean Journal of Food Science and Technology
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• v.8 no.2
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• pp.63-69
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• 1976

The changes in lysine availability during soybean fermentation were determined by the chemical analysis method as well as the biological methods with rat. The FDNB-reactive lysine determined by the difference (TLMI) method indicated that cooking and Meju fermentation reduced the lysine availability of soybean, but the subsequent ripening restored the availability to the same level of the raw soybean. On the other hand, the Biological Value, NPU, NER and the Relative lysine availability of the rat experiments showed a general decrease in the lysine availability of soybean during the ripening process as well as Meju fermentation.

• Journal of the Korean Society of Food Culture
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• v.28 no.6
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• pp.640-650
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• 2013

Soy sauce, a basic ingredient in Asian cuisine, is made of fermented soybeans, salt, water, and barley or wheat flour. The sensory characteristics of soy sauce are not only determined through its main ingredients but also by various flavor compounds produced during the fermentation process. This study was conducted to identify the sensory attributes of five different commercial soy sauce samples that differ in Meju types (traditional Meju or modified Meju) and usage types. Thirty three sensory attributes, including appearance (1), odor (16), flavor (14), and mouthfeel (2) attributes, were generated and evaluated by eight trained panelists. The collected data were analyzed by analysis of variance and principal component analysis. There were significant differences in the intensities of all sensory attributes among the soy sauce samples. Soy sauce made with traditional Meju had high intensity of fermented fish, beany, musty odors and salt, Cheonggukjang, fermented fish flavors. Whereas two soy sauces made with modified Meju were strong in alcohol, sweet, Doenjang, roasted soybean flavors. Two soy sauces for soup made with modified Meju had medium levels of briny, sulfury, fermented odors and bitter, chemical flavors and biting mouthfeel characteristic.

• 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.

• 한국균학회소식:학술대회논문집
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• 2014.05a
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• pp.25-25
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• 2014

Koji molds are comprised of yellow, black and white. Black and white koji molds were recently re-visited by this author and it is concluded that they consists of Aspergillus luchuesnsis, A. niger and A. tubingensis, and the most important species for alcoholic beverage production is A. luchuensis. In the case of yellow koji mold, it is comprised of Aspergillus oryzae, A. sojae and A. tamari. In the case of A. sojae, the species is scarcely isolated from nature and rarely used for industry in Korea. Aspergillus tamari is often isolated from traditional Korean Meju, a fermented soybean product, and the classification of the species is clear. However, in the case of A. oryzae, differentiation between A. oryzae and A. flavus is still in controversy. In this study, we collected 415 strains of Aspergillus flavus/oryzae complex from air, rice straw, soybean, corn, peanut, arable soil and Meju in Korea and we examined the aflatoxin producing capacity of the strains. The norB-cypA, omtA and aflR genes in the aflatoxin biosynthesis gene cluster were analyzed. We found that 367 strains (88.4%) belonged to non-aflatoxigenic group (Type I of norB-cypA, IB-L-B-, IC-AO, or IA-L-B- of omtA, and AO type of aflR), and only 48 strains (11.6%) belonged to aflatoxin-producible group (Type II of norB-cypA, IC-L-B+/B- or IC-L-B+ of omtA, and AF type of aflR). In the case of A. flavus/oryzae strains from Meju, almost strains (178/192, 92.7%) belonged to non-aflatoxigenic group and only 14 strains (7.3 %) belonged to aflatoxin-producible group. It is proposed in this study that non-aflatoxigenic strain from Meju is classified as A. oryzae, considering that Meju is food material.