title: Molecular and oenological characterization of Touriga Nacional non-Saccharomyces yeasts.
abstract: OBJECTIVE
  The aim of this study was to evaluate non-Saccharomyces yeasts isolated from spontaneous fermenting musts of Touriga Nacional (TN), one of the most important Portuguese red grape variety, to improve and diversify TN wines.
  
  
  RESULTS
  Two hundred and seventy nine isolates were assigned to 11 yeast species by conventional molecular and growth tests. Starmerella bacillaris was the most frequently detected yeast species, followed by Hanseniaspora guilliermondii and Hanseniaspora uvarum. Twenty-three isolates from 10 species were selected for oenological study, namely fermentation performance, physicochemical and quantitative descriptive sensory analysis of the wines produced. A significant species effect was observed for most of the variables evaluated, some species generating wines with quite interesting aromas.
  
  
  CONCLUSIONS
  Candida diversa and S. bacillaris isolates produced wines with higher overall quality, higher balance and more intense and diverse aroma. Furthermore, S. bacillaris isolates generated wines with enhanced TN typical aroma, such as bergamot, violet and rock-rose, and were thus regarded as the most promising for improving TN wines.
  
  
  CONCLUSIONS
  This study revealed the diversity of wine aroma profiles generated by non-Saccharomyces yeast isolates. This knowledge is particularly important given the growing trend from industry to use non-Saccharomyces yeasts as a tool for improving and diversifying the sensory characteristics of wine.
authors.affiliation: Laboratório de Enologia, U.I.S. Tecnologia e Segurança Alimentar, Instituto Nacional de Investigação Agrária e Veterinária, I.P., Quinta da Almoínha, Dois Portos, Portugal.
authors.forename: A
authors.initials: A
authors.lastname: Teixeira
authors.forename: I
authors.initials: I
authors.lastname: Caldeira
authors.forename: F L
authors.initials: FL
authors.lastname: Duarte
mesh_terms: D005285:Fermentation; D012903:Smell; D027843:Vitis; D014920:Wine / Q000032:analysis / Q000382:microbiology*; D015003:Yeasts / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*
keywords: Touriga Nacional; descriptive sensory analysis; non-Saccharomyces; oenological characterization; rRNA gene restriction profiles