title: Population analysis of biofilm yeasts during fino sherry wine aging in the Montilla-Moriles D.O. region.
abstract: Fino is the most popular sherry wine produced in southern Spain. Fino is matured by biological aging under a yeast biofilm constituted of Saccharomyces cerevisiae yeasts. Although different S. cerevisiae strains can be identified in such biofilms, their diversity and contribution to wine character have been poorly studied. In this work, we analyse the flor yeast population in five different wineries from the Montilla-Moriles D.O. (Denominación de Origen) in southern Spain. Yeasts present in wines of different ages were identified using two different culture-dependent molecular techniques. From 2000 individual yeast isolates, five different strains were identified with one of them dominating in four out of the five wineries analysed, and representing 76% of all the yeast isolates collected. Surprisingly, this strain is similar to the predominant strain isolated twenty years ago in Jerez D.O. wines, suggesting that this yeast is particularly able to adapt to such a stressful environment. Fino wine produced with pure cultures of three of the isolated strains resulted in different levels of acetaldehyde. Because acetaldehyde levels are a distinctive characteristic of fino wines and an indicator of fino aging, the use of molecular techniques for yeast identification and management of yeast populations may be of interest for fino wine producers looking to control one of the main features of this wine.
authors.affiliation: Centro Andaluz de Biología del Desarrollo, Universidad Pablo de Olavide, de Sevilla-CSIC-Junta de Andalucía, Sevilla, Spain.
authors.forename: Miriam
authors.initials: M
authors.lastname: Marin-Menguiano
authors.affiliation: Centro Andaluz de Biología del Desarrollo, Universidad Pablo de Olavide, de Sevilla-CSIC-Junta de Andalucía, Sevilla, Spain.
authors.forename: Sandra
authors.initials: S
authors.lastname: Romero-Sanchez
authors.affiliation: Centro Andaluz de Biología del Desarrollo, Universidad Pablo de Olavide, de Sevilla-CSIC-Junta de Andalucía, Sevilla, Spain.
authors.forename: Ramón R
authors.initials: RR
authors.lastname: Barrales
authors.affiliation: Centro Andaluz de Biología del Desarrollo, Universidad Pablo de Olavide, de Sevilla-CSIC-Junta de Andalucía, Sevilla, Spain. Electronic address: joibecor@upo.es.
authors.forename: Jose I
authors.initials: JI
authors.lastname: Ibeas
mesh_terms: D000079:Acetaldehyde / Q000032:analysis*; D018441:Biofilms / Q000254:growth & development*; D021901:DNA, Intergenic / Q000235:genetics; D005285:Fermentation / Q000502:physiology*; D005516:Food Microbiology; D061353:Food Storage / Q000379:methods; D016533:Mycological Typing Techniques / Q000379:methods*; D012150:Polymorphism, Restriction Fragment Length; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism*; D013030:Spain; D014920:Wine / Q000032:analysis / Q000382:microbiology*
chemical_list: D021901:DNA, Intergenic; D000079:Acetaldehyde
keywords: Biofilm; Biological aging; Flor yeast; Saccharomyces cerevisiae; Sherry wine; Velum; Yeast