• Journal of Microbiology and Biotechnology
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• v.25 no.9
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• pp.1493-1501
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• 2015

A Bacillus species, EMD4, with strong antibacterial activity was isolated from ganjang (soy sauce) and identified as B. subtilis. B. subtilis EMD4 strongly inhibited the growth of B. cereus ATCC14579 and B. thuringiensis ATCC33679. The antibacterial activity was stable at pH 3-9 but inactive at pH 10 and above. The activity was fully retained after 15 min at 80℃ but reduced by 50% after 15 min at 90℃. The activity was completely destroyed by proteinase K and protease treatment, indicating its proteinaceous nature. The bacteriocin (BacEMD4) was partially purified from culture supernatant by ammonium sulfate precipitation, and Q-Sepharose and Sephadex G-50 column chromatographies. The specific activity was increased from 769.2 AU/mg protein to 8,347.8 AU/mg protein and the final yield was 12.6%. The size of BacEMD4 was determined to be 3.5 kDa by Tricine SDS-PAGE. The N-terminal amino acid sequence was similar with that of Subtilosin A. Nucleotide sequencing of the cloned gene confirmed that BacEMD4 was Subtilosin A. BacEMD4 showed bactericidal activity against B. cereus ATCC14579.

• Journal of Food Hygiene and Safety
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• v.34 no.3
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• pp.296-302
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• 2019

Ganjang-gejang (soy sauce-marinated crab) is a ready-to-eat (RTE) seafood and is also one of the most popular traditional dishes in Korea. It is generally prepared by washing raw blue crabs and then preserving them in soy sauce. Since this process does not involve cooking or any treatment with heat, it is difficult to control the microbiological quality of the final product. Thus, the objectives of this study were to compare the efficacies of various sanitizers in eliminating microorganisms on raw blue crab during the washing step and to evaluate the effectiveness of chitosan on the inhibition of microbial growth in the ganjang-gejang during storage. The raw blue crabs were submerged in chlorinated water (50 mg/L), peracetic acid (40 mg/L), acetic acid (5%) and lactic acid (5%) for 10 min at $25^{\circ}C$, respectively. The blue crabs treated with 5% acetic acid were marinated with soy sauce containing 0.5 and 1% of soluble chitosan, followed by storing them at 4 and $12^{\circ}C$ for up to 30 days. Results show that 5% acetic acid reduced the microbial populations on the blue crabs by 1.5 log CFU/g, which was significantly higher than those of other treatments. Based on these results, 5% acetic acid was selected for the washing step. The microbial populations of all ganjang-gejang samples significantly increased to about 8.0 CFU/g at $12^{\circ}C$ for 7 days. At $4^{\circ}C$, the microbial populations of the products containing 1% chitosan increased by about 2.9 CFU/g for 20 days, which were significantly lower than those (4.2-4.5 log CFU/g) of the products without and with 0.5% chitosan. Thus, these results suggest that 5% acetic acid washing of raw blue crabs and the addition of 1% chitosan in ganjang-gejang could improve the microbiological quality of the final products under refrigerated condition.

• Korean Journal of Food Science and Technology
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• v.46 no.4
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• pp.522-525
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• 2014

The effects of temperature and inosine monophosphate (IMP) on the germination of artificially inoculated Bacillus cereus spores in ganjang, doenjang, and gochujang sauces were investigated. The pH and salt concentration of the sauces were as follows: ganjang (4.84, 7.45%), doenjang (4.26, 5.07%), and gochujang (3.54, 3.24%), respectively. Treatment at $40^{\circ}C$ or $80^{\circ}C$ resulted in a B. cereus growth of 0.8 log CFU/g in ganjang sauce; this concentration increased to 2.25 log CFU/g and 1.21 log CFU/g, respectively, when 10 mM IMP was added. Compared with that for ganjang sauce, the germination effect was comparatively lower for doenjang sauce by 10 mM IMP+$40^{\circ}C$ treatment (0.46 log CFU/g) and 10 mM IMP+$80^{\circ}C$ treatment (0.85 log CFU/g). However, no germination effect was noted for gochujang sauce by any treatment in this study. Therefore, the results suggested that pH is an important factor affecting spore germination in sauces.

• Journal of Nutrition and Health
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• v.45 no.6
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• pp.577-587
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• 2012

This study was conducted to investigate the consumption pattern and perception of traditional soy sauce and soybean paste products in male and female adults aged 19 and over in Seoul and Gyeonggi-do areas in order to promote the development of the products' industry. The survey was conducted between October 1 to October 15, 2011 among 294 male and female adults aged 19 years and over in Seoul and Gyeonggi-do areas. The gender distribution of the subjects was 33.3% males and 66.7% females. For a perception on traditional dietary life, the degree for enjoying meals with cooked rice as the staple food revealed that 32.3% of the subjects responded 'strongly agree'. The intake frequency of traditional soy sauce and soybean paste products in the subjects of the study showed that in the case of doenjang, 49.7% of the participants consumed it twice a week and 21.4% consumed it once a week. For gochujang, 59.9% consumed it twice a week and 19.0% consumed it once a week. The perception on the preparation method for traditional soy sauce and soybean paste products showed a low level for traditional soy sauce and soybean paste products. The reason for purchasing traditional foods showed that 77.6% of the subjects made purchases for convenience and 8.2% purchased it for its small package. For the subjects, the priority for purchasing traditional soy sauce and soybean paste products was as follows: in the first rank, ingredients & origin made up 33.7% and price comprised of 26.2% of the priority. Regarding satisfaction for soy sauce and soybean paste products in the market, the degree of satisfaction was high for gochujang. With regard to gender difference, female subjects showed a significantly lower satisfaction for cheonggukjang and kuk-ganjang, and a significantly higher satisfaction for chin-ganjang, compared to the male subjects. The results of the study depicted that consumer's requirement was high for traditional soy sauce and soybean paste products in the market, particularly for the safety of the products in the market. Consumer satisfaction was relatively positive yet, some efforts are needed in order to improve the quality of cheonggukjang and kuk-ganjang.

• Korean journal of food and cookery science
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• v.21 no.6 s.90
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• pp.800-812
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• 2005

This study selected and classified the representative foods for diversifying Korean traditional foods in the globa1 market and derived the superior factor of each food by consumer survey (n=744). The superiority of Korean traditional foods was generally recognized as being in the order of 'Nutritional value' > 'Dietary culture' > 'Material' > 'Taste.' Kimchi, Tteok/Hangwa, and grilled foods were regarded as potent Korean traditional foods for global consumers. The survey about the superior factors of representative Korean traditional foods produced the following results. The superior factor of Bibimbap, Mandu, Jangachi, Joeotgal, Namul muchim Salad, Naengchae, and Ganjang was 'Variety of material or cuisine', that of Bap, Jut Samguetang, Seolleongtang, Kimchi, Doenjang, and Sikcho was 'Nutritional value', that of Naengmyeon, Kalguksu, Bulgogi, Pyeonyuk, Jeongol, Gochujang, Tteot and Sjkhae/Sujeonggwa was Taste', and that of Hangwa, Hwachae, Gujulpan, and Sinsunro was 'Appearance'. The superior factors of representative Korean traditional foods showed the following differences by age and gender, The superior factor in Mandu was 'Taste' by the subjects aged below 30 but 'Variety' by the subjects aged above 30; that in Pyeonyuk and Jeongol was 'Variety' in 31-40 year olds and those aged above 51, while it was 'Taste' in others. The superior factor of Kimchi was 'Nutritional value' by the subjects aged below 40,'Taste'in 41-50 year. olds, and 'Variety' by the subjects aged above 50, that of Namul muchim was 'Nutritional value' by the subjects aged below 20 and 'Variety'by the subjects aged above 20, and that of Naengchae was' Taste'by the subjects aged below 20 and 'Variety' by the subjects aged above 20. The superior factor of Gochujang was 'Taste' by the subjects aged below 50 and 'Variety 'by the subjects aged above 50, that of Ganjang was 'Variety' by the subjects aged below 30 and 'Taste' by the subjects aged above 30, that of Sikcho was 'Variety' by the subjects aged below 30 and 'Nutritional value' by the sutjects aged above 30. The superior factor of Doenjang was 'Nuttritional value' in all ages. The superior factors of Hangwa and Sikhae/Sujeonggwa were 'Appearance' and 'Taste' in all ages, and that of Hwachae was 'Taste' by the subjects aged below 30 and' Appearance' by the subjects aged above 30. The perception by gender was statistically differed for traditional foods such as Bap, Bibimbap, Kalguksu, Bulgogi, Pyeonyuk Jangachi, Gochujang, Ganjang, Sikhae/Sujeonggwa, Hwachae, and Gujulpan.

• Journal of Life Science
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• v.32 no.10
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• pp.803-811
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• 2022

Despite the importance of traditional Korean fermented foods, little is known about the microbial communities and diversity of fermented soy products. To gain insight into the unexplored microbial communities of both Doenjang (DJ) and Ganjang (GJ) that may contribute to the fermentation in Korean traditional foods, we carried out next-generation sequencing (NGS) based on the V3-V4 region of 16S rDNA gene analysis. The alpha diversity analysis results revealed that both the Shannon and Simpson diversity indices were significantly different between the two groups, whereas the richness indices, including ACE, CHAO, and Jackknife, were not significant. Firmicutes were the most dominant phylum in both groups, but several taxa were found to be more abundant in DJ than in GJ. The proportions of Bacillus, Kroppenstedtia, Clostridium, and Pseudomonas and most halophiles and halotolerant bacteria, such as Tetragenococcus, Chromohalobacter, Lentibacillus, and Psychrobacter, were lower in DJ than in GJ. Linear discriminant effect size (LEfSe) analysis was carried out to discover discriminative functional biomarkers. Biomarker discovery results showed that Bacillus and Tetragenococcus were identified as the most important features for the classification of subjects to DJ and GJ. Paired-permutational multivariate analysis of variance (PERMANOVA) further revealed that the bacterial community structure between the two groups was statistically different (p=0.001).

• Journal of Microbiology and Biotechnology
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• v.28 no.5
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• pp.663-670
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• 2018

The present study focused on the production, characterization, and in vitro prebiotic evaluation of an exopolysaccharides (EPS) from Bacillus sonorensis MJM60135 isolated from ganjang (fermented soy sauce). Strain MJM60135 showed the highest production ($8.4{\pm}0.8g/l$) of EPSs compared with other isolates that were screened for EPS production based on ropy culture morphology. Furthermore, MJM60135 was cultured in 5 L of medium and the EPS was extracted by ethanol precipitation. The emulsification activity of the EPS was higher in toluene than in o-xylene. Fourier transform infrared spectroscopy analysis showed the presence of hydroxyl and carboxyl groups and glycosidic linkages. The isolated EPS contained mannose and glucose, as observed by thin-layer chromatography analysis of the EPS hydrolysate. Lactic acid bacteria (LAB) and pathogenic E. coli K99 and Salmonella enterica serovar Typhimurium were tested for their growth utilizing the EPS from B. sonorensis MJM60135 as the sole carbon source for its possible use as a prebiotic. All the tested LAB exhibited growth in the EPS-supplied medium compared with glucose as carbon source, whereas the pathogenic strains did not grow in the EPS-supplied medium. These findings indicate that the EPS from B. sonorensis MJM60135 has potential application in the bioremediation of hydrocarbons and could also be used as a prebiotic.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.3
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• pp.243-249
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• 2017

Crabs are a popular seafood item. However, they can harbor many microorganisms, heavy metals, radioactivity, and benzo(a)pyrene, which are potential health risks to humans. The objective of this study was to assess the potential of swimming crabs for use in foods such as Ganjang-gejang, by measuring their sanitary biological and chemical properties. Viable microbial cell counts in swimming crab samples were $3.4{\times}10^2-6.7{\times}10^4CFU/g$, but no coliform, Escherichia coli, or pathogenic bacteria, such as Vibrio parahaemolyticus, Enterohemorrhagic E. coli, Listeria monocytogenes, Staphylococcus aureus, or Salmonella spp., were detected. Heavy metal concentrations in swimming crab samples were non-detectable to 0.112 mg/kg for total mercury, non-detectable to 0.435 mg/kg for lead, and 0.115-0.836 mg/kg for cadmium. Benzo(a)pyrene concentrations ranged from $0.025-0.060{\mu}g/kg$, and the volatile basic nitrogen content ranged from 8.7-15.6 mg/100 g. No radioactivity was detected in samples. These results suggest that swimming crabs are viable for use in seafood products.

• Journal of Microbiology and Biotechnology
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• v.34 no.4
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• pp.863-870
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• 2024

Meju, a fermented soybean brick, is a key component in soybean foods like doenjang and ganjang, harboring a variety of microorganisms, including bacteria and fungi. These microorganisms significantly contribute to the nutritional and sensory characteristics of doenjang and ganjang. Amplicon-based next-generation sequencing was applied to investigate how the microbial communities of meju fermented at low and high temperatures differ and how this variation affects the microbial communities of doenjang, a subsequently fermented soybean food. Our metagenomic data showed distinct patterns depending on the fermentation temperature. The microbial abundance in the bacterial community was increased under both temperatures during the fermentation of meju and doenjang. Weissella was the most abundant genus before the fermentation of meju, however, it was replaced by Bacillus at high temperature-fermented meju and lactic acid bacteria such as Weissella and Latilactobacillus at low temperature-fermented meju. Leuconostoc, Logiolactobacillus, and Tetragenococcus gradually took over the dominant role during the fermentation process of doenjang, replacing the previous dominant microorganisms. Mucor was dominant in the fungal community before and after meju fermentation, whereas Debaryomyces was dominant under both temperatures during doenjang fermentation. The dominant fungal genus of doenjang was not affected regardless of the fermentation temperature of meju. Strong correlations were shown for specific bacteria and fungi linked to specific fermentation temperatures. This study helps our understanding of meju fermentation process at different fermentation temperatures and highlights different bacteria and fungi associated with specific fermentation periods which may influence the nutritional and organoleptic properties of the final fermented soybean foods doenjang.

• The Korean Journal of Food And Nutrition
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• v.25 no.3
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• pp.460-482
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• 2012

On the basis of the cookbooks and Data Base of the Korean Classics(http://db.itkc.or.kr/itkcdb/mainIndexIframe.jsp), this paper analyzed the fermented soybean listed in the general documents of the Chosun Dynasty(1392~1897) and the Goryeo Dynasty(918~1392). In the Goryeo Dynasty, there are 15 kinds of Jang(soybean paste or solution), among which are Jang (soybean paste fermented by mold)(6 documents), Yeomgjang, Yeomshi(2), and Gaejang(1). However, the cookbook at that time is defunct. The Goryeo Court relieved the famine-stricken people by proving them with Jang. In the Chosun Dynasty, 111 kinds of Jang were listed in the general documents, and 153 kinds in cookbooks. There were 55 kinds of general Jang, such as Jang(204), Yeomjang(63), Chojang, Goojang(7), and Gaejang(6), are listed in the general documents, and in the cookbooks, there are 55 kinds of Jang, such as Sookwhangjang(9 cookbooks), Daemaekjang(8), Myeonjang(8), Saengwhangjang (8), and Yooinjang(8), and among them, 13 kinds belong to the Chinese origin. A total of 9 Kinds of Ganjang(soybean solution fermented by mold), such as Soojang(30), Cheongjang(23), Gamjang(8), and Ganjang(3) are found in the general documents. In the cookbooks, 12 kinds of Jang, as Cheongjang(10), Cheonrijang(4), Ganjang(3), and etc., are listed. There were 9 kinds of Gochoojang(red pepper-soybean paste), such as Chojang(12), Gochojang(3), and etc., are listed in the general documents, and 9 kinds as Gochojang(7), Manchojang(7), rapid Manchojang(4), and etc., are in the cookbooks. In addition, 16 Kinds of Yookjang(fermented soybean-meat paste) as Haejang(15), Hyejang(11), Yookjang(11), and etc., are found in the documents, and 22 kinds as Nanjang(9), Gejang(6), Yookjang(5), Shoigogijang(4), and etc., are in the cookbooks. Eighteen Kinds of Shi(soybean paste fermented by bacteria) as Yeomshi(40), Shi(35), Shijang(6), and etc., are recorded in the documents, and 19 kinds as Jeonkookjang(6), Shi(4), Sooshijang(4), and etc., are in the cookbooks, and among them 11 kinds belong to the Chinese origin. Six kinds of Jipjang(aqueous soybean paste) as Jipjang(7), Uoopjang(4), Pojang (2), Jangzoop(2) are recorded in the documents, and 15 kinds as Jipjang(9), Zoopjeo(7), and Hajeoljipjang(5) are in the cookbooks. Soybean paste, or solution for relieving hunger is not recorded in the documents. However, the Chosun court, for the purpose of relieving famine-stricken people, used general Jang. Such 21 Jang to relieve the famine-stricken people as Pojang(7), rapid Jang(6), and Sasamgilgyeongjang(4) are listed in the cookbook. Geonjang(dried soybean paste), Nanjang (egg-soybean paste), Doojang(soybean paste), Maljang(random soybean paste), Myeonjang(wheate-soybean paste), Sodoojang (red bean-soybean paste), Yookjang(soybean-meat paste) and Jang(soybean paste) are recorded in the documents, as well as in the cookbooks. Chinese-original Jang and Shi are recorded in the cookbooks, with no list in the general documents. Therefore, it seems that it didn't pass down to the general public.