title: A flow-cytometric method for determination of yeast viability and cell number in a brewery.
abstract: A flow-cytometric assay, using the fluorescent dye, oxonol, for the simultaneous determination of yeast cell viability and cell number is described. The assay was optimised, and trialed at a brewery for 6 months. The flow-cytometry assay offered a substantially reduced error in viability determination, compared to methylene blue which is the industry standard for measuring viability. Further, by calculating yeast cell number at the same time, this assay provides a reliable method for determining pitching rate, allowing increased quality control of subsequent fermentations.
authors.affiliation: Centre for Fluorimetric Applications in Biotechnology, Department of Biological Sciences, Macquarie University, North Ryde, 2109, Sydney, NSW, Australia. aboyd@rna.bio.mq.edu.au
authors.forename: Andrew R
authors.initials: AR
authors.lastname: Boyd
authors.forename: Thusitha S
authors.initials: TS
authors.lastname: Gunasekera
authors.forename: Paul V
authors.initials: PV
authors.lastname: Attfield
authors.forename: Kristina
authors.initials: K
authors.lastname: Simic
authors.forename: Scott F
authors.initials: SF
authors.lastname: Vincent
authors.forename: Duncan A
authors.initials: DA
authors.lastname: Veal
mesh_terms: D002452:Cell Count; D005434:Flow Cytometry / Q000379:methods*; D005456:Fluorescent Dyes / Q000032:analysis; D008751:Methylene Blue / Q000494:pharmacology; D015203:Reproducibility of Results; D013194:Staining and Labeling / Q000379:methods; D014920:Wine / Q000382:microbiology*; D015003:Yeasts / Q000166:cytology* / Q000187:drug effects
chemical_list: D005456:Fluorescent Dyes; D008751:Methylene Blue