• Proceedings of the Korean Society of Toxicology Conference
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• 2001.10a
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• pp.13-14
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• 2001

Doenjang (Korean fermented soybean paste) is one of important fermented foods in Korea. Doenjang has been traditionally manufactured from meju which is fermented rectangular shape of crushed cooked soybeans. The main microorganisms involved for meju fermentation are Bacillus subtilis and molds such as Rizopus sp., Mucor sp. and Aspergillus sp. We have already reported that Doenjang is free from mycotoxin, especially, aflatoxin B$_1$contamination during the manufacturing process of the Deonjang.(omitted)

• 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.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.6
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• pp.818-824
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• 2003

This study was carried out to select Meju of a good quality through general composition analysis, organoleptic evaluation, and to conduct isolation, identification, and growth characteristics of main strain related to fermentation from selected Meju. Moisture and crude protein of Meju were 7.2∼28.8% and 32.7∼42.3%, respectively. The amino nitrogen contents of Kyongbuk and Chonbuk Mejus were 770.8 mg% and 239.9 mg%, respectively. And also, free amino acid and glutamic acid contents of Doenjangs made from Chonbuk and Kyongbuk Mejus were 4,169.6 mg% and 499.4 mg%, respectively. The result of sensory evaluation of Mejus collected from several regions showed Kyongbuk was the most suitable Meju in items of color, flavor, appearance and overall (p<0.05). The typical properties of B. lichenifomis NH20 strain isolated from Kyongbuk Meju showed gram positive, aerobic rod cell and motility. As major component among its cellular fatty acid composition, $C_{15:0}$ anteiso fatty acid, $C_{15:1}$ iso fatty acid, $C_{17:0}$ anteiso fatty acid, and $C_{17:0}$ iso fatty acid were 30.7, 28.9, 13.3 and 11.2%, respectively. It showed the same identification coefficient (0.653) compared to the standard strain. Therefore, it was identified to be B. licheniformis NH20 according to Bergey's Manual of Systematic Bacteriology and its fatty acid profiles. The optimum pH, temperature, salt content, and culture time of B. licheniformis NH20 were 7.0, 32$^{\circ}C$, 2%, and 9 hours, respectively.ctively.

• Korean journal of food and cookery science
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• v.13 no.2
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• pp.92-98
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• 1997

Ethyl carbamate is an animal carcinogen and a by-product of fermentation. Since the highest level of ethyl carbamate was found in a traditional soy sauce sample in the previous study, soysauce was prepared in varying experimental conditions with three kinds of meju originated from different area of the country to investigate the factors affecting ethyl carbamate formation. The sample analysis methods included a semi-purification with solid-phase extraction and detection by GC-MS at SIM mode using m/z 62 fragment ion. Among the investigated factors, which includes source meju, bringing length, salt content, irradiation of visible light during bringing or storage, and storage length, source meju and storage length showed most profound effect on the formation of ethyl carbamate. Irradiation of visible light for 12 hours a day during storage lowered the concentration of ethyl carbamate compared to the soysauce kept in the dark. Meanwhile irradiation during the bringing as well as the degree of salt contents showed no effect.

• Korean Journal of Food Science and Technology
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• v.31 no.3
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• pp.757-763
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• 1999

Based on the previous studies, R. stolonifer was selected for the model system of Korean soy sauce preparation process, using the fermented soybean. The system of meju fermentation was refined; the optimal conditions of temperature and relative humidity were $25^{\circ}C$ and 90%, respectively. The optimal temperature for soy sauce fermentation was evaluated to the $25^{\circ}C$ and, in the latter half of the fermentation, some aeration was observed to positively affect the sensory evaluation of soy sauce. In the sensory evaluation, the soy sauce fermented with B. subtilis and A. sojae was showed to be better than one fermented with R. stolonifer. Conditions of the pasteurization and ultrafiltration process were also established for industrialization of the soy sauce. Finally, the standard systems using the soybean fermented was, by the industrial scales, proposed for Korean traditional soy sauces.

• Korean Journal of Food Science and Technology
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• v.16 no.4
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• pp.403-407
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• 1984

The purpose of this study was to investigate the changes of phytic acid content and phytase activity and the interactions between phytic acid and minerals in the preparation of Meju (fermented steamed soybean mash with molds). Meju contained significantly lower phytic acid and higher phytase activity than both raw and cooked soybeans. This seems to be the result of degradation of phytic acid by phytase produced during preparation of Meju by Aspergillus oryzae. Fe, Zn, Ca contents of soybeans were not changed either by cooking or fermentation. However, these minerals in the retentate of ultrafiltration were significantly lower in Meju than in raw and cooked soybeans. This result indicated that there are lower mineral-phytic acid complex in Meju than in raw and cooked soybeans, which might contribute to higher bioavailability of these minerals in Meju.

• 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 Science and Nutrition
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• v.45 no.6
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• pp.880-888
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• 2016

Changes in quality characteristics of gochujang prepared with different ingredients (white rice, barley, sorghum and millet, bamboo salt) and meju starters were studied. The gochujang samples were fermented for 6 weeks at $40^{\circ}C$ and analyzed for changes in their physicochemical properties and sensory characteristics. Eight different gochujang samples were prepared: WR-SS-AB, WR-SS-ABL, WR-BS-AB, WR-BS-ABL, MG-SS-AB, MG-SS-ABL, MG-BS-AB, MG-BS-ABL (WR: white rice, MG: mixed grains, SS: solar salt, BS: bamboo salt, AB: Aspergillus oryzae/Bacillus subtilis starter meju, ABL: Aspergillus oryzae/Bacillus subtilis/Lactobacillus plantarum starter meju). There were significant differences between experimental groups in terms of moisture content, pH, acidity, and color value. All gochujang samples showed increased moisture contents and pH as well as increased acidity and amino-type nitrogen during fermentation. MG-BS-ABL showed the highest contents of amino-type nitrogen and free amino acids after 6 weeks of fermentation compared with other experiment groups. In addition, MG-BS-ABL showed the highest sensory analysis score, including appearance, flavor, taste, and overall acceptability after the fermentation of samples. Based on the results, MG-BS-ABL exhibited similar quality characteristics as general gochujang but showed the highest sensory scores and contents of amino-type nitrogen and free amino acids. These results might be due to the high protein contents of mixed grains and high mineral contents of bamboo salt and fermented products from mixed probiotic starters.

• Korean Journal of Food Science and Technology
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• v.9 no.2
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• pp.131-137
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• 1977

This study was conducted to examine the changes of pH, proteolytic enzymic activity, and every kind of nitrogen compounds during their fermentation of the three groups of meju for 90days. Among the three groups, the first group was conventional Korean meju which was proved to be good quality (sample J), the second group was prepared with soybean paste using B. subtilis (sample K), and the third group was an improved meju which was fermented with the soybean and wheat (7 : 3) mixtured paste with Asp. sojae (sample L). These groups were analyzed at an interval of 10 day and the results are summarized as follows: 1) The pH of the all three groups was lowered from $6.45{\sim}6.75\;to\;4.85{\sim}5.20$ in just the 30 days and maintained the weak acidity during this fermentation. 2) The proteolytic enzymic activity was increased as soon as the three groups of meju were fermented and marked the maximum value in 30 days. The maximum value of the three groups of meju J.K. and L was 147, 112, and 52 respectively. The proteolytic enzymic activity of sample J and K was decreased to 23.5 and 20.5 in 20 days, while that of sample L was decreased to 18.0 in 40 days, and maintained the volues to the end of fermentation for 90 days. The conventional meju J and the improved meju K showed sparkling activity at the pH 7, while the activity of improved meju L was strong at the pH 10. 3) The PAA-N content of sample J and K was increased and reached to the peak point with 1.55% and 1.49% respectively in 60 days. But the sample L marked the maximum value with 1.28% after 80 days. 4) The amino-N content of sample J was increased and reached to 0.36% after 60 days, and that of sample K and L was increased and reached to 0.29% and 0.21% respectively after 40 days. After reaching to the peak point, the contents were decreased. 5) The content of ammonia-N was most abundant in sample K which was fermented with soybean paste using B. subtilis. 6) The peptide-N content of sample K and L was increased after decreasing in the middle of fermentation period, while that of sample J was increased gradually during fermentation. 7) The changes of nitrogen compounds were seemed to complete in 60 days of fermentation.

• Korean Journal of Food Science and Technology
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• v.21 no.6
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• pp.876-883
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• 1989

In order to investigate the index component and basis for the shelf-life of the grain share improved Meju, the effect of the storage time and package on the quality of Meju and soy sauce were studied during 90 days storage at $30^{\circ}C$. Also, sensory evaluation for the soy sauces from Meju with various storage time were carried out. During the storage period, moisture content, amylase and protease activity were decreased, on the other hand, the contents of amino-nitrogen and ammonia-nitrogen were increased. Among these components, protease activity was found the major index component for quality control because it was the most important component for soy sauce fermentation and the most changeable component of Meju during the storage period. According to the sensory test, the quality of soy sauce was agreed well with the protease activity of Meju, and the soy sauce from longer storage Meju was inferior organoleptic quality to that from shorter Meju. By the storage quality test, protease activity showed the highest value in 15 days storage Meju and decreased gradually with storage time passed. The basis of protease activity for quality control was 200 (O.D. at 660 nm/g). which was 50% of the initial activity And it was known that the shelf-life of the grain shape improved Meju was about 90 days . It was also shown that the storage in package did not affect noticeably to prolong the shelf-life of Meju on this study.