| Title: | "The effect of salt concentrations on the fermentation of doenjang, a traditional Korean fermented soybean paste" |
| Author(s): | Chun BH; Kim KH; Jeong SE; Jeon CO; |
| Address: | "Department of Life Science, Chung-Ang University, Seoul, 06974, Republic of Korea. Department of Life Science, Chung-Ang University, Seoul, 06974, Republic of Korea. Electronic address: cojeon@cau.ac.kr" |
| ISSN/ISBN: | 1095-9998 (Electronic) 0740-0020 (Linking) |
| Abstract: | "Four sets of doenjang (traditional Korean fermented soybean paste) with 9%, 12%, 15%, and 18% solar salt concentrations were prepared and their pH, microbial abundances and communities, metabolites, and volatile compounds were analyzed periodically during the entire fermentation. The speeds of decrease in pH and increase in microbial abundances, representing microbial activity, were higher during early fermentation in lower (9% and 12%) salt doenjang. Microbial abundances in 15% and 18% salt doenjang were significantly lower than in the 9% and 12% salt doenjang, indicating low microbial activity. Community analysis revealed that Bacillus, Staphylococcus, and Clostridium and Aspergillus, Scopulariopsis, Fusarium, Mucor, and Penicillium, which might be derived from doenjang-meju used for preparing doenjang, were identified as major bacterial and fungal genera, respectively, in all doenjang samples. Weissella, Tetragenococcus, Oceanobacillus, and Debaryomyces, not dominant in doenjang-meju, were also identified as major groups in low salt doenjang. Metabolite analysis showed that amino acid profiles were relatively similar independent of salt concentrations and microbial growth, indicating important roles of indigenous proteases present in doenjang-meju, not microbial activity during doenjang fermentation, in amino acid production. The metabolism of free sugars to organic acids and biogenic amine production were greater in lower salt doenjang, which might be associated with the growth of microbes, particularly lactic acid bacteria. A higher level of and more diverse volatile compounds were identified in lower salt doenjang, indicating close association with microbial growth. This study provides a deeper understanding of doenjang fermentation and insight into the development of low salt doenjang" |
| Keywords: | Acids/analysis/metabolism Amino Acids/analysis/metabolism Bacteria/classification/genetics/isolation & purification/metabolism Biogenic Amines/analysis/metabolism Fermentation Fermented Foods/analysis/*microbiology Fungi/classification/genetics/isolation; |
| Notes: | "MedlineChun, Byung Hee Kim, Kyung Hyun Jeong, Sang Eun Jeon, Che Ok eng England 2019/11/11 Food Microbiol. 2020 Apr; 86:103329. doi: 10.1016/j.fm.2019.103329. Epub 2019 Sep 14" |
