title: Influence of the dominance of must fermentation by Torulaspora delbrueckii on the malolactic fermentation and organoleptic quality of red table wine.
abstract: Torulaspora delbrueckii can improve wine aroma complexity, but its impact on wine quality is still far from being satisfactory at the winery level, mainly because it is easily replaced by S. cerevisiae yeasts during must fermentation. New T. delbrueckii killer strains were selected to overcome this problem. These strains killed S. cerevisiae yeasts and dominated fermentation better than T. delbrueckii non-killer strains when they were single-inoculated into crushed red grape must. All the T. delbrueckii wines, but none of the S. cerevisiae wines, underwent malolactic fermentation. Putative lactic acid bacteria were always found in the T. delbrueckii wines, but none or very few in the S. cerevisiae wines. Malic acid degradation was the greatest in the wines inoculated with the killer strains, and these strains reached the greatest dominance ratios and had the slowest fermentation kinetics. The T. delbrueckii wines had dried-fruit/pastry aromas, but low intensities of fresh-fruit aromas. The aroma differences between the T. delbrueckii and the S. cerevisiae wines can be explained by the differences that were found in the amounts of some fruity aroma compounds such as isoamyl acetate, ethyl hexanoate, ethyl octanoate, and some lactones. This T. delbrueckii effect significantly raised the organoleptic quality scores of full-bodied Cabernet-Sauvignon red wines inoculated with the killer strains. In particular, these wines were judged as having excellent aroma complexity, mouth-feel, and sweetness.
authors.affiliation: Departamento de Ciencias Biomédicas (Área de Microbiología), Facultad de Ciencias, Universidad de Extremadura, 06071 Badajoz, Spain. Electronic address: mramirez@unex.es.
authors.forename: Manuel
authors.initials: M
authors.lastname: Ramírez
authors.affiliation: Departamento de Ciencias Biomédicas (Área de Microbiología), Facultad de Ciencias, Universidad de Extremadura, 06071 Badajoz, Spain.
authors.forename: Rocío
authors.initials: R
authors.lastname: Velázquez
authors.affiliation: Departamento de Ciencias Biomédicas (Área de Microbiología), Facultad de Ciencias, Universidad de Extremadura, 06071 Badajoz, Spain.
authors.forename: Matilde
authors.initials: M
authors.lastname: Maqueda
authors.affiliation: Estación Enológica, Junta de Extremadura, 06200 Almendralejo, Spain.
authors.forename: Emiliano
authors.initials: E
authors.lastname: Zamora
authors.affiliation: Departamento de Biología Vegetal, Ecología y Ciencias de la Tierra, Facultad de Ciencias, Universidad de Extremadura, 06071 Badajoz, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: López-Piñeiro
authors.affiliation: Departamento de Ciencias Biomédicas (Área de Microbiología), Facultad de Ciencias, Universidad de Extremadura, 06071 Badajoz, Spain.
authors.forename: Luis M
authors.initials: LM
authors.lastname: Hernández
mesh_terms: D061046:Biological Control Agents / Q000378:metabolism*; D005285:Fermentation / Q000502:physiology*; D005421:Flavoring Agents / Q000378:metabolism; D008293:Malates / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000254:growth & development* / Q000378:metabolism; D012677:Sensation; D055319:Torulaspora / Q000235:genetics / Q000378:metabolism*; D027843:Vitis / Q000378:metabolism; D014920:Wine / Q000382:microbiology*
chemical_list: D061046:Biological Control Agents; D005421:Flavoring Agents; D008293:Malates; C030298:malic acid
keywords: Aroma; Ethyl hexanoate (PubChem CID: 31265); Ethyl octanoate (PubChem CID: 7799); Isoamyl acetate (PubChem CID: 31276); Killer; Malolactic fermentation; Red wine; Torulaspora; Yeast; γ-Ethoxy-butyrolactone (PubChem CID: 356063)