• Preventive Nutrition and Food Science
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• v.4 no.1
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• pp.38-42
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• 1999

Antimutagenic effects of 5 kinds of kochujang(Korean red pepper soybean paste) samples compared with doenjang(Korean soy paste) were studied using the Ames test with Salmonella typhimurium TA100 and the SOS chromotest, with E. Coli PQ37. Th eantimutatenic effects of methanol extracts from red pepper powder and meju(fermented soybean) powder, the major ingredients of the kochujang,were also evaluated for the mutagenicity of aflatoxin B1 (AFB1) in the Ames assay. The methanol extracts from the kochujang samples showed lower antimutagenicities than those of doenjang against AFB1 and N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in the Ames assay. Traditional kochujang I and II exhibited strong antimutagenic activity against AFB1 and MNNG. The traditional kochujang samples against MNNG were aslo observed in the SOS chromotest system with the same fashions as shown in the Ames mutagenicity test. The methanol extracts from meju powder had the strongest inhibitory effects on mutabenicity induced by AFB1, however, those form red pepper powder showed lower inhibition rate than kochujang. These results suggest that traditional kochujang exhibit higher antimutagenic acitivity than the commercial variety, and that meju powder seems to be one of the major antimutagenic components in kochujang.

• Korean journal of food and cookery science
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• v.14 no.5
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• pp.463-467
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• 1998

This study was carried out in order to analyze the changes in general compounds, reducig sugar, nitrogen compounds of traditional Korean soy sauce with varying Meju Type (Traditional Meju, Modified Meju) and ripening periods and to investigate correlation between sensory characteistics via sensory evaluation of soy sauce samples. And to investigate actual conditions and attitude of comsumer of soy suace.

• Korean Journal of Food Science and Technology
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• v.29 no.6
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• pp.1166-1174
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• 1997

This study was designed to investigate the changes in physicochemical and sensory characteristics of traditional kochujang during aging, which was prepared with a different meju fermented for various periods of time. The non-volatile organic acid contents in all samples gradually increased up to 90 days of fermentation. Kochujang prepared with a 40-day-fermented meju had $1.14{\sim}2.54$ times highter organic acid content after 90 days of aging as compared to other kochujang preparations. The most abundant free sugars were found to be glucose and fructose representing $82.27{\sim}100%$ of total free sugar contents in kochujang. 17 kinds of free amino acid including Glu, Asp and Met were found in traditional kochujang aged for 90 days. Glu was noted as the most contributing amino acid to the brothy taste of kochujang in the light of increasing ratio and content of Glu among free amino acids during aging. The total free amino acid contents of kochujang increased with an Increase in fermentation time of meju. Results of sensory evaluation revealed that kochujang prepared with a 40-day-fermented meju was best in terms of flavor and taste. These results suggest that kochujang prepared with a 40-day-fermented meju had the highest quality in terms of physicochemical and sensory characteristics of kochujang.

• 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.

• 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.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.

• Food Science and Biotechnology
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• v.17 no.2
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• pp.442-445
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• 2008

Meju, a major ingredient of doenjang which is a popular Korean traditional fermented soyfood, was manufactured by fermenting steamed soybeans in natural environment in which steamed soy was exposed to airborne microorganism, in particular, fungi. Total isoflavone content was reduced from 1,849 mg/kg of cooked soy to 816 mg/kg of meju at the $90^{th}$ day of fermentation. Total glycosides and aglycones of isoflavones in meju were 1,827 and 22 mg/kg at 0 day and changed into 487 and 329 mg/kg at the 90th day of fermentation, respectively. Meanwhile, the ratio of glycosides to aglycones of isoflavones was not changed during aging of doenjang but remained relatively constant with 592 and 644 mg/kg aglycones at the 0 and $160^{th}$ day, respectively. When cooked soy was fermented with Aspergillus oryzae and Aspergillus flavus, isoflavone profiles were significantly different from each other while A. oryzae caused more extensive metabolism of isoflavones than A. flavus.

• Applied Biological Chemistry
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• v.49 no.1
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• pp.7-14
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• 2006

This study was carried out to examine the quality characteristics of soybean pastes made of Meju with mold-producing pretense isolated from traditional Meju. The changes in moisture content, enzyme activity (amylase, protease, lipase), reducing sugar, amino-type nitrogen contents and anti-oxidant activity were investigated during the aging period. The moisture contents decreased gradually with time. Amylase activity decreased during the aging period while pretense and lipase activities increased until 30-45 days of aging, but decreased thereafter, Especially pretense activity in soybean paste with mold was greater than that in the control. Amino-type nitrogen and ammoniacal nitrogen contents increased, but reducing sugar contents decreased with time. Amino-type nitrogen contents were greater in soybean paste made of Meju with isolated mold than those in the control. Antioxidative activity was also confirmed in soybean paste.

• Journal of Nutrition and Health
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• v.46 no.6
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• pp.493-502
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• 2013

In this study, we designed to confirm the dietary effect of anti-obesity of fermented soybean curd residue (FSCR; SCR-Meju; Biji-meju) by A. oryzae, which is well known as a Korean traditional meju microbe. We observed that body weight gain, serum and hepatic lipid profile, as well as the activity of ROS generating enzyme and ROS scavenging enzyme in high-fat diet induced obese mice fed experimental diet (SCR and SCR-meju). Body weight gain and epididymal fat weight of HC (high-fat diet control) was markedly higher than that of NC (Normal control). Conversely, body weight gain and epididymal fat weight of the SCR (Biji) and SCR-meju (Biji-meju) group was significantly lower than that of HC; these of the SCR-meju group was lower than that of the SCR group. Furthermore, serum TG and total-cholesterol and LDL-cholesterol contents of SCR and SCR-meju groups were lower than that of HC, and HDL-cholesterol level of the SCR-meju group was significantly higher than that of HC. In conclusion, although precise mechanisms of the antiobese effects of SCR-meju in this study are unknown, the present study provides an experimental evidence that SCR-meju may prevent obesity and obesity related metabolic syndromes, such as hyperlipidemia, hypertension and diabetes, and liver disease by high-fat diet. Nevertheless, further study in this filed will be needed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.2
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• pp.343-350
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• 2002

This study was conducted to standardize the manufacturing process of doenjang. The preparation methods, kinds and levels of the ingredients were determined by the statistical surveys of literatures obtained from cooking books, scientific papers and doenjang manufacturing factories. The standardized preparation of fermentation methods of doenjang were classified into two large groups, that were traditional and modified (commercialized) methods. Most soybeans used in doenjang preparation were the large size. To prepare traditional doenjang, soybeans were cleaned, scaled and cooked for 2 hrs at atmospheric pressure. These cooked soybeans were crushed in water and molded as brick shape. The molded soybean was dried for 2 days in the air, hung up by rice straw and fermented for 30~60 days under natural environmental condition (called meju). Recently soybean grain meju that inoculated with Asp. oryzae also frequently used to make traditional doenjang. The fermented meju was brined with a ratio of meju : salt : water = 18.4 : 14.6 : 67.0 and the meju-brine mixtures were ripened for 2 months. When the meju-brine mixture was fully fermented, it was separated into liquid and solid parts. The crushed solid part was further ripened in a separated pottery for 60 days and become doenjang. The liquid part was filtered, boiled and used as soy sauce. In modified commercial doenjang preparation, soybeans were cocked by autoclaving and then cooled about to 3$0^{\circ}C$. Separately, steamed barley grains or wheat flour were inoculated with 0.2% Asp. oryzae and incubated for 3 days at 3$0^{\circ}C$ and mixed with the crooked soybeans, salt, and water (soybean : salt : starch : water = 39.8 : 12.5 : 22.6 : 25.1). These mixtures were ripened for 30 days at 3$0^{\circ}C$. It seems that the manufacturing process of traditional doenjang needs to be more industrialized, whereas, the commercial doenjang preparation is going to adapt the traditional processing method of doenjang.