| Summary: | The application of yeast strains that are low producers of sulfur compounds is actually required by winemakers for the production of organic wine. This purpose could be satisfied using a native <i>Saccharomyces cerevisiae</i> strain improved for oenological aptitudes. Moreover, to improve the aromatic complexity of wines, sequential fermentations carried out with <i>S. cerevisiae</i>/non-<i>Saccharomyces</i> yeast is widely used. For these reasons, in the present work an improved native <i>S. cerevisiae</i> low producer of sulfite and sulfide compounds was evaluated in pure and in sequential fermentation with a selected <i>Torulaspora delbrueckii</i>. Additionally, the influence of grape juices coming from three different vintages under winery conditions was evaluated. In pure fermentation, improved native <i>S. cerevisiae</i> strain exhibited a behavior related to vintage, highlighting that the composition of grape juice affects the fermentation process. In particular, an increase in ethyl octanoate (vintage 2017) and phenyl ethyl acetate (vintage 2018) was detected. Moreover, isoamyl acetate was highly consistent and could be a distinctive aroma of the strain. The sequential fermentation <i>T. delbrueckii</i>/<i>S. cerevisiae</i> determined an increase in aroma compounds such as phenyl ethyl acetate and ethyl hexanoate. In this way, it was possible to produce Verdicchio wine with reduced sulfites and characterized by a peculiar aromatic taste.
|
|---|