A dark matter in sake brewing: Origin of microbes producing a Kimoto-style fermentation starter

Bibliographic Details
Title: A dark matter in sake brewing: Origin of microbes producing a Kimoto-style fermentation starter
Authors: Kohei Ito, Ryo Niwa, Ken Kobayashi, Tomoyuki Nakagawa, Genki Hoshino, Yuji Tsuchida
Source: Frontiers in Microbiology, Vol 14 (2023)
Publisher Information: Frontiers Media S.A., 2023.
Publication Year: 2023
Collection: LCC:Microbiology
Subject Terms: Japanese sake, microbial fermentation, Kuratsuki, microbiome, Kimoto-style, Microbiology, QR1-502
More Details: IntroductionIn Kimoto-style fermentation, a fermentation starter is produced before the primary brewing process to stabilize fermentation. Nitrate-reducing bacteria, mainly derived from brewing water, produce nitrite, and lactic acid bacteria such as Leuconostoc can proliferate because of their tolerance toward low temperature and their low nutritional requirements. Later, Lactobacillus becomes the dominant genus, leading to weakly acidic conditions that contribute to control yeasts and undesired bacterial contaminants. However, the sources of these microorganisms that play a pivotal role in Sake brewing have not yet been revealed. Thus, comprehensive elucidation of the microbiome is necessary.MethodsIn this study, we performed 16S rRNA amplicon sequencing analysis after sampling from floor, equipment surfaces, and raw materials for making fermentation starters, including koji, and water in Tsuchida Sake brewery, Gunma, Japan.ResultsAmplicon sequence variants (ASVs) between the external environments and the fermentation starter were compared, and it was verified that the microorganisms in the external environments, such as built environments, equipment surfaces, and raw materials in the sake brewery, were introduced into the fermentation starter. Furthermore, various adventitious microbes present in the fermentation starter of early days and from the external environments were detected in a nonnegligible proportion in the starter, which may impact the taste and flavor.DiscussionThese findings illuminate the uncharacterized microbial dark matter of sake brewing, the sources of microbes in Kimoto-style fermentation.
Document Type: article
File Description: electronic resource
Language: English
ISSN: 1664-302X
Relation: https://www.frontiersin.org/articles/10.3389/fmicb.2023.1112638/full; https://doaj.org/toc/1664-302X
DOI: 10.3389/fmicb.2023.1112638
Access URL: https://doaj.org/article/19040c5a00e54759a20e99e9be933045
Accession Number: edsdoj.19040c5a00e54759a20e99e9be933045
Database: Directory of Open Access Journals
More Details
ISSN:1664302X
DOI:10.3389/fmicb.2023.1112638
Published in:Frontiers in Microbiology
Language:English