| Summary: | <i>Starmerella bacillaris</i> is a non-<i>Saccharomyces</i> yeast proposed for must fermentation together with <i>Saccharomyces cerevisiae</i> because of its high glycerol and moderate volatile acidity production. Furthermore, it was demonstrated that the same <i>S. bacillaris</i> strains that possess interesting technological properties exhibited antifungal activity against <i>Botrytis cinerea</i>, suggesting the release of this yeast in the vineyard. To obtain a positive effect during the following winemaking process, the maintenance of suitable concentrations of <i>S. bacillaris</i> is essential. Therefore, to obtain information on the survival of <i>S. bacillaris</i>, a small-scale field trial was performed. One week before the harvest, two different concentrations of <i>S. bacillaris</i> (10<sup>6</sup> and 10<sup>7</sup> cells/mL) were sprayed on Pinot grigio bunches, and the strain concentration was monitored by means of qPCR during the subsequent fermentation process. In addition, the combined effect of different winemaking techniques was evaluated, i.e., the vinification of juice, juice with marc and cryomaceration treatment. Results demonstrated that, under the tested conditions, <i>S. bacillaris</i> released in the vineyard remained viable for one week on grape bunches and increased glycerol content during the subsequent fermentation process. Different vinification protocols influenced cell concentrations. In particular, the cryomaceration treatment, due to the use of low temperature, supported <i>S. bacillaris</i> growth due to its cryotolerant aptitude. The collected data open new perspectives on the control of alcoholic fermentation, involving both vineyard and cellar management.
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