title: Yeast ecology of vineyards within Marsala wine area (western Sicily) in two consecutive vintages and selection of autochthonous Saccharomyces cerevisiae strains.
abstract: In this work, the yeast ecology associated with the spontaneous fermentation of Grillo cultivar grapes from 10 vineyards was analyzed from grape harvest till complete consumption of must sugars. The microbiological investigation started with the plate count onto two culture media to distinguish total yeasts (TY) and presumptive Saccharomyces (PS). Yeasts were randomly isolated and identified by a combined genotypic approach consisting of restriction fragment length polymorphism (RFLP) of 5.8S rRNA gene and 26S rRNA and sequencing of D1/D2 domain of the 26S rRNA gene, which resulted in the recognition of 14 species belonging to 10 genera. The distribution of the yeasts within the vineyards showed some differences in species composition and concentration levels among 2008 and 2009 vintages. Due to the enological relevance, all Saccharomyces cerevisiae isolates were differentiated applying two genotypic tools (interdelta analysis and microsatellite multiplex PCR of polymorphic microsatellite loci) that recognized 51 strains. Based on the low production of H(2)S, acetic acid and foam, ethanol resistance, growth in presence of high concentrations of potassium metabisulphite (KMBS) and CuSO(4) and at low temperatures, 14 strains were selected and used as starter to ferment grape must at 13 °C and 17 °C in presence of 100 mg/L of KMBS. Three strains (CS160, CS165 and CS182) showed optimal technological aptitudes.
authors.affiliation: DEMETRA Department, University of Palermo, Viale delle Scienze 4, 90128 Palermo, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Settanni
authors.forename: Ciro
authors.initials: C
authors.lastname: Sannino
authors.forename: Nicola
authors.initials: N
authors.lastname: Francesca
authors.forename: Rosa
authors.initials: R
authors.lastname: Guarcello
authors.forename: Giancarlo
authors.initials: G
authors.lastname: Moschetti
mesh_terms: D019342:Acetic Acid / Q000378:metabolism; D003470:Culture Media / Q000494:pharmacology; D004271:DNA, Fungal / Q000032:analysis / Q000235:genetics; D000431:Ethanol / Q000378:metabolism / Q000494:pharmacology; D005285:Fermentation / Q000187:drug effects; D005838:Genotype; D006862:Hydrogen Sulfide / Q000378:metabolism; D018895:Microsatellite Repeats / Q000235:genetics; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D012335:RNA, Ribosomal / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000145:classification* / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification*; D012802:Sicily; D013447:Sulfites / Q000494:pharmacology; D013696:Temperature; D027843:Vitis / Q000378:metabolism / Q000382:microbiology*; D014920:Wine / Q000382:microbiology*
chemical_list: D003470:Culture Media; D004271:DNA, Fungal; D012335:RNA, Ribosomal; D013447:Sulfites; D000431:Ethanol; C005199:potassium metabisulfite; D019342:Acetic Acid; D006862:Hydrogen Sulfide