title: Evaluation of microbial diversity in the pilot-scale beer brewing process by culture-dependent and culture-independent method.
abstract: OBJECTIVE
  In the brewing industry, microbial management is very important for stabilizing the quality of the product. We investigated the detailed microbial community of beer during fermentation and maturation, to manage beer microbiology in more detail.
  
  
  RESULTS
  We brewed a beer (all-malt) and two beerlike beverages (half- and low-malt) in pilot-scale fermentation and investigated the microbial community of them using a next-generation sequencer (454 GS FLX titanium), quantitative PCR, flow cytometry and a culture-dependent method. From 28 to 88 genera of bacteria and from 9 to 38 genera of eukaryotic micro-organisms were detected in each sample. Almost all micro-organisms died out during the boiling process. However, bacteria belonging to the genera Acidovorax, Bacillus, Brevundimonas, Caulobacter, Chryseobacterium, Methylobacterium, Paenibacillus, Polaromonas, Pseudomonas, Ralstonia, Sphingomonas, Stenotrophomonas, Tepidimonas and Tissierella were detected at the early and middle stage of fermentation, even though their cell densities were low (below approx. 10(3) cells ml(-1) ) and they were not almost detected at the end of fermentation.
  
  
  CONCLUSIONS
  We revealed that the microbial community of beer during fermentation and maturation is very diverse and several bacteria possibly survive during fermentation.
  
  
  CONCLUSIONS
  In this study, we revealed the detailed microbial communities of beer using next-generation sequencing. Some of the micro-organisms detected in this study were found in beer brewing process for the first time. Additionally, the possibility of growth of several bacteria at the early and middle stage of fermentation was suggested.
authors.affiliation: National Research Institute of Brewing (NRIB), Higashi-Hiroshima, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Takahashi
authors.forename: Y
authors.initials: Y
authors.lastname: Kita
authors.forename: K
authors.initials: K
authors.lastname: Kusaka
authors.forename: A
authors.initials: A
authors.lastname: Mizuno
authors.forename: N
authors.initials: N
authors.lastname: Goto-Yamamoto
mesh_terms: D001419:Bacteria / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D001515:Beer / Q000382:microbiology*; D044822:Biodiversity; D056890:Eukaryota / Q000302:isolation & purification; D005285:Fermentation; D005516:Food Microbiology
keywords: beer; culture-dependent method; fermentation; flow cytometry; microbiota; next-generation sequencing; quantitative PCR