title: Outlining a future for non-Saccharomyces yeasts: selection of putative spoilage wine strains to be used in association with Saccharomyces cerevisiae for grape juice fermentation.
abstract: The use of non-Saccharomyces yeasts that are generally considered as spoilage yeasts, in association with Saccharomyces cerevisiae for grape must fermentation was here evaluated. Analysis of the main oenological characteristics of pure cultures of 55 yeasts belonging to the genera Hanseniaspora, Pichia, Saccharomycodes and Zygosaccharomyces revealed wide biodiversity within each genus. Moreover, many of these non-Saccharomyces strains had interesting oenological properties in terms of fermentation purity, and ethanol and secondary metabolite production. The use of four non-Saccharomyces yeasts (one per genus) in mixed cultures with a commercial S. cerevisiae strain at different S. cerevisiae/non-Saccharomyces inoculum ratios was investigated. This revealed that most of the compounds normally produced at high concentrations by pure cultures of non-Saccharomyces, and which are considered detrimental to wine quality, do not reach threshold taste levels in these mixed fermentations. On the other hand, the analytical profiles of the wines produced by these mixed cultures indicated that depending on the yeast species and the S. cerevisiae/non-Saccharomyces inoculum ratio, these non-Saccharomyces yeasts can be used to increase production of polysaccharides and to modulate the final concentrations of acetic acid and volatile compounds, such as ethyl acetate, phenyl-ethyl acetate, 2-phenyl ethanol, and 2-methyl 1-butanol.
authors.affiliation: Dipartimento di Biotecnologie Agrarie, Università degli Studi di Firenze, Via Donizetti 6, 50144 Firenze, Italy. domizio@unifi.it
authors.forename: Paola
authors.initials: P
authors.lastname: Domizio
authors.forename: Cristina
authors.initials: C
authors.lastname: Romani
authors.forename: Livio
authors.initials: L
authors.lastname: Lencioni
authors.forename: Francesca
authors.initials: F
authors.lastname: Comitini
authors.forename: Mirko
authors.initials: M
authors.lastname: Gobbi
authors.forename: Ilaria
authors.initials: I
authors.lastname: Mannazzu
authors.forename: Maurizio
authors.initials: M
authors.lastname: Ciani
mesh_terms: D000085:Acetates / Q000032:analysis / Q000378:metabolism; D019342:Acetic Acid / Q000032:analysis / Q000378:metabolism; D018920:Coculture Techniques; D000431:Ethanol / Q000378:metabolism; D005285:Fermentation; D007218:Industrial Microbiology; D012441:Saccharomyces cerevisiae / Q000145:classification / Q000235:genetics / Q000502:physiology; D027843:Vitis / Q000378:metabolism / Q000382:microbiology; D014920:Wine / Q000032:analysis / Q000382:microbiology*; D015003:Yeasts / Q000145:classification / Q000235:genetics / Q000502:physiology*
chemical_list: D000085:Acetates; D000431:Ethanol; C007650:ethyl acetate; D019342:Acetic Acid