• 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.10 no.1
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• pp.63-72
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• 1978

Effect of shapes (noodle, grain and brick types) and strains (Aspergillus oryzae and Aspergillus sojae) of Meju (microorganism inoculated soybean substrate for fermentation) on the quality of soy sauce was investigated. Generally, the highest protease activity was found in the noodle type-Meju inoculated Asp. sojae during Meju preparation and soy sauce brewing, however, the lowest value was noted in brick type. Meju inoculated Asp. oryzae. Similar tendency was found on the contents of total solid, total nitrogen, amino-nitrogen, nitrogen digestion yield and amino-nitrogen ratio during soy sauce brewing. No effect was shown on the reducing sugar content, alcohol formation, pH, buffer action and salt content according to different Meju types during soy sauce brewing. Organoleptic tests on the color, taste and flavor of soy sauce after 3 months brewing with various Meju scored in the order of noodle type-Asp. sojae soy sauce (best quality), noodle type-Asp, orzae soy sauce, brick type-Asp. sojae soy sauce and brick type-Asp. oryzae-soy sauce (worst quality).

• Applied Biological Chemistry
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• v.13 no.1
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• pp.35-42
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• 1970

Five samples of Korean native Maeju(fermented soy-bean mash) loaves which were collected each from Kyunggi, Chungchung, Kangwon, Cholla and Kyungsang-Do were examined for their fermenting microorganisms. The results of taxonomic and ecological studies of fermentation microorganisms in these Maeju loaves were as the fellows. (1) The fungus flora grew only is the outer layer of Maeju loaves. Miscellaneous molds, 3 species of Mucor, 2 species of Pericallium., one species each of Scopulariopsis and Aspergillus, were isolated. None of them seemed exclusively predominant to be able to designate as the ecologically significant. (2) The bacterial flora which consisted of two species, Bacillus subtilis and Bacillus pumilus were distributed uniformly in th a entire Maeju loaves. The inner parts of Maeju loaves were especially inhabited solely by these bacterial flora. Probably the Korean native Maeju fermentation could be characterized by these bacterial flora. A Staphylococcus species was also isolated probably as a casual contaminant. (3) The yeasts, Rhodotorula flava and Torulopsis dattila, were isolated from Maeju loaves though their ecological significance was not clear. (4) The ecological aspects of fermentation microbes in the outer and inner parts of Maeju loaves were apparently different, consequently different fermentation processes might have occurred in these two parts and it brought quite different final outlooks in the final matured Maeju loaves. The outer part, rather rigid and dry, retained the light brown color of boiled soy-bean; whereas the inner part, soft and sticky, showed dark brown color indicating severe chemical changes. (5) The aflatoxin producing mold, Aspergillus oryzae was isolated from one sample among 5 of Maeju loaves. In addition to the low probability of isolability from Maeju loaves samples, since this mold grew only in the outer layer of Maeju loaves with such a low population density, about $10^4/g$, perhaps the aflatoxin problem in Korean native soysauce may not be critical.

• The Korean Journal of Mycology
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• v.27 no.4 s.91
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• pp.312-317
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• 1999

In order to study the antitumoral effect of meju extracts, which was made with a single inoculum of the microorganism, the cytotoxicity effects on several human leukemia cells such as promyelocytic leukemia cell (HL60), histiocytic lymphoma cell (U937) and acute T-cell leukemia Jurkat cell, and lymphocyte were analyzed by MTT assay. Twenty one microbes, mainly fungal genera, were isolated from Korean traditional mejus of different regions. From those collected isolates, meju was manufactured and extracted with 80% methanol, respectively. Meju methanol extracts exhibited low activites in cytotoxicity tests on HL60 cell, but high antitumoral effects of meju methanol extracts were shown on U937 and Jurkat cells. Meju methanol extracts made with a genera of Mucor, Absidia and Aspergillus showed prominant cytotoxic activities, especially. However all these extracts had no inhibitory effects on the cell growth of lymphocyte under the same conditions.

• Korean Journal of Food Science and Technology
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• v.22 no.1
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• pp.82-87
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• 1990

To investigate the shelf-life of the brick share improved Meju, the effect of the storage time and packaged storage on the quality of Meju and soy sauce were studied during 90 days storage at $30^{\circ}C$. During the storage period, pretense activity was rapidly increased, and it reached the maximum value after 30 days of storage and then decreased gradually with storage time. By the sensory evaluation, the soy sauce from Meju which was longer storage was increased its brown color but less sensory quality on taste and flavor. The sensory evaluation score of soy sauces were closely related to the value of protease activity of Meju, So, it was shown that the protease activity was also the major index component on the quality control for the brick shape improved Meju. The protease activity of brick shape Meju was lower during Meju making but decreased slowly during storage period than that of grain shape meju. The values of protease of Meju after 30 days storage were 359 (O.D. at 660 nm/g) in non-packaged, 349 in packaged Meju and after 180 days storage were 207,205, respectively. It was shown that the shelf-life of the brick shape improved Meju was about 180 days by the basis (protease activity: 200 O.D. at 660nm/g) for quality control from the grain shape Meju, and it was longer than that of grain shape Meju. It was also shown that the packaged storage did not prolong the shelf-life of the brick shape improved Meju.

• Korean Journal of Food Science and Technology
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• v.8 no.1
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• pp.12-18
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• 1976

Fermented soybean Mejus were prepared in the laboratory with varying lengths of fermentation and the changes in the Chemical composition during the Meju making were determined. The moisture of cooked soybean was gradually evaporated during the Meju fermentation, and after 2 months of fermentation the water level reached to the level of the raw soybean. The concentrations of crude fat, crude protein and ash of the dry matter of soybean did not change considerably during soaking, cooking and Meju fermentation of up to 3 months, whereas carbohyrates decreased significantly during soaking and Meju fermentation. The percentage retention of the nutrients were 58% for carbohydrates and 93% for crude fat and crude protein. The nitrogen solubility of soybean decreased drastically during cooking, from 79% to 21%, while Meju fermentation increased it to approximately 30% in the first week and this level remained constant for the duration of the fermentation. The concentration of free amino nitrogen in total nitrogen of soybean decreased during cooking, from 7% to 3%, but fermentation of Meju liberated it to the level of raw soybean. The concentration of free amino-nitrogen in the total-N of soybean was increased by cooking and further increased during Meju fermentation. The amino acid pattern of soybean did not change significantly during soaking, cooking and the Meju fermentation up to 3 months. Serine and the basic amino acids, lysine, arginine and histidine, decreased to the range $81{\sim}87%$ of the raw soybean during the first month of Meju fermentation and thereafter remained almost constant. The total amino acid per 16g nitrogen was 99 g incooked soybean and 93 g in 1 month Meju, indicating a 6% reduction.

• Applied Biological Chemistry
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• v.46 no.3
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• pp.195-200
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• 2003

Methods of adding barley malt as source of carbohydrates and enzymes in the production of kanjang in order to improve it's tastes and qualities were investigated. Soybean meju, soybean-malt meju and soybean meju cummalt was mashed with 20% salt brine in the ratio of 1:3 respectively, matured and analyzed the chemical compositions of the soy sauce mash samples for 150 days of maturing. Organoleptic evaluations for the matured soy sauce samples were done. The higher total nitrogen, TCA soluble nitrogen, O.D. at 500 nm, pure extract and lactic acid content could be observed with the soy sauce mash made of soybean-malt meju than those of contrast one from the beginning of the mashing throughout to the whole maturing period of 150 days. The higher the content of malt in the soybean-malt meju, the higher those content in the mash. But the lower content of those compositions in the soy sauce mash made of soybean meju cum malt than those in the contrast was found. The highest scores in all the sensory characteristics including 7.56 points, which were significantly different from that of contrast soy sauce at 5% level, in overall palatability were obtained by the soy sauce made of soybean-malt meju added with 30% malt in the organoleptic evaluations.

• Korean Journal of Food Science and Technology
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• v.29 no.6
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• pp.1158-1165
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• 1997

This study was designed to investigate the changes in microflora and enzyme activities of traditional kochujang during aging, which was prepared with a meju fermented for various periods of time. The number of bacteria was highest in all samples after 30 days of fermentation at $20^{\circ}C$, while that of mold in kochujang prepared with a 40-day- or 60-day-fermented meju was highest at 15th day of aging when yeast appeared. The activities of carbohydrases and proteases were highest in kochujang prepared with a 40-day-fermented meju followed by a 60-day-fermented meju. These results suggest that kochujang prepared with a meju aged for 40 days had the highest quality in terms of physicochemical, microbiological and enzyme activities of kochujang during fermentation.

• Microbiology and Biotechnology Letters
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• v.11 no.3
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• pp.241-248
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• 1983

Lupin seed was used to make Meju, the fermentation starter for Korean soybean sauce and paste in substitution for soybean and the fermentation characteristics were compared with those of soybean. Mejus were prepared by in-oculating Asp. oryzae on the cooked whole beans. The dried Mejus were used for making fermented bean sauce and paste by mixing with brine and subsequent ripening for 4 weeks. In general the protease activity and amylase activity-during ripening were higher in lupin seed Meju than those of soybean Meju. The increase in protease activity correlated to the increase in $\alpha$-amino nitrogen content of the fermented paste and sauce. The development of dark-brown color of the sauce during ripening faster with lupin seed Meju compared to soybean Meju. In sensory evaluation the flavor score of lupin seed sauce and paste was slightly lower than that of soybean products but the overall quality of fermented lupin seed sauce was acceptable.

• Applied Biological Chemistry
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• v.35 no.4
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• pp.248-253
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• 1992

Volatile flavor components of soybean pastes, manufactured with traditional Meju and improved Meju, were extrated by simultaneous steam distillation-extraction apparatus and concentrated at atmosphere press. The concentrates were investigated GC-sniff evaluation by preparative gas chromatograph, and then analyzed and identified by GC/MS and Kovats retention index. Thirty nine components, including 11 alcohols, 4 aldehydes, 2 pyrazines, 4 acids, 3 fuans, 3 phenols, 3 esters, 3 hydrocarbons, 1 ketone, 5 miscellous ones were confirmed in soybean paste manufactured with traditional Meju. Twenty one components, including 4 alcohols, 2 aldehydes, 2 pyrazines, 2 acids, 1 fuan, 2 esters, 1 hydrocarbon, 2 ketones, 4 miscellous ones were confirmed in soybean paste manufactured with improved Meju. Ten components such as 3-methyl-1-butanol, 4-methyl-3-heptanol, trimethyl-pyrazine, 1-octen-3-ol, 2-furancarboxaldehyde, tetramethyl-pyrazine, benzaldehyde, 3-methyl-butanoic acid, naphthalene, 2-ethyl-3-methyl-oxetane were identified together in soybean pastes manufactured with traditional Meju and improved Meju.