Characterization of the β‐Glucosidase Activity Produced by Enological Strains of Non‐Saccharomyces Yeasts

The β‐glucosidase activities of 20 wine‐related non‐ Saccharomyces yeasts were quantified, characterized, and assessed for their efficiency in releasing aroma‐enhancing compounds during the winemaking process. Of these enzymatic activities, the β‐glucosidase activity of Debaryomyces pseudopolymorphus revealed the most suitable combination of properties in terms of functionality at wine pH, resistance to wine‐associated inhibitory compounds (glucose, ethanol, and sulfur dioxide), high substrate affinity, and large aglycone‐substrate recognition. Its potential as a wine aroma‐enhancing enzyme was confirmed by the significantly increasing concentrations of free volatiles (citronellol, nerol, and geraniol) during the fermentation of Chardonnay juice inoculated with both D. pseudopolymorphus and a widely used commercial starter culture strain of Saccharomyces cerevisiae , VIN13.