Ecological Distribution and Oenological Characterization of Native <i>Saccharomyces cerevisiae</i> in an Organic Winery

Abstract

The relation between regional yeast biota and the organoleptic characteristics of wines has attracted growing attention among winemakers. In this work, the dynamics of a native Saccharomyces cerevisiae population was investigated in an organic winery. In this regard, the occurrence and the persistence of native S. cerevisiae were evaluated in the vineyard and winery and during spontaneous fermentation of two nonconsecutive vintages. From a total of 98 strains, nine different S. cerevisiae biotypes were identified that were distributed through the whole winemaking process, and five of them persisted in both vintages. The results of the oenological characterization of the dominant biotypes (I and II) show a fermentation behavior comparable to that exhibited by three common commercial starter strains, exhibiting specific aromatic profiles. Biotype I was characterized by some fruity aroma compounds, such as isoamyl acetate and ethyl octanoate, while biotype II was differentiated by ethyl hexanoate, nerol, and β-damascenone production also in relation to the fermentation temperature. These results indicate that the specificity of these resident strains should be used as starter cultures to obtain wines with distinctive aromatic profiles.

Keywords

• native <i>S. cerevisiae</i>
• <i>S. cerevisiae</i> biodiversity
• spontaneous fermentation
• molecular characterization
• winery environment