Effect of Non-Saccharomyces Species Monocultures on Alcoholic Fermentation Behavior and Aromatic Profile of Assyrtiko Wine

Abstract

Six wild-type non-Saccharomyces strains, belonging to the species Zygosaccharomyces bailii, Priceomyces carsonii, Trigonopsis californica, and Pichia manshurica, were evaluated for white wine production using Assyrtiko grapes from Santorini in Greece. Fermentation kinetics, in terms of glucose and fructose consumption and sensory analysis, was first employed to test the enological potential of the yeast strains. Based on their performance, two strains of Z. bailii (Zb-A19Y5 and Zb-K29Y2) and one strain of T. californica (Tc-A9Y1) selected for further analysis. The selected strains were tested in larger fermentation volumes for sugar consumption, while the produced wines were assessed for classical enological parameters, volatile compounds (GC/MS), and sensory analysis. Tc-A9Y1 could lead to dry wine (1 g/L of residual sugars) with 1.6 vol (12%) less alcohol than the other experimental wines. The wines that were fermented with the strain Zb-K29Y2 exhibited very high concentrations of isoamyl alcohol (604.33 ± 76.8 mg/L), but at the same time, they were characterized by low fruity notes. None of the produced wines presented any off-flavor aromas. Exploiting non-Saccharomyces strains with great fermentation capacity, which are able to produce high-quality wines and adapted to global warming conditions, is a new challenge for the wine industry.