Impact of mixed S. cerevisiae strains on the production of volatiles and estimated sensory profiles of Chardonnay wines

Abstract: The global wine industry is mostly reliant on the use of active dry yeasts to conduct wine fermentations. The use of single industrial yeasts, however, may result in the loss of complexity or uniqueness of the wine bouquet; the option of fermenting grape musts with multiple active dried yeast strains could enhance the complexity and quality of wines. Two novel Burgundian Saccharomyces cerevisiae strains (C2, C6) were compared with six industrial yeast strains for fermentation of Chardonnay must. The volatile compounds in the wines were identified and quantified using gas chromatography–mass spectrometry. The concentrations of 18 volatile compounds (higher alcohols, ethyl esters, acetate esters, acetaldehyde, acetic acid) were compared using analysis of variance and radar diagrams. The concentration of volatile compounds in wines produced by industrial and Burgundian strains differed significantly. Principal component analyses of the volatile compounds (higher alcohols, ethyl esters, acetate esters) in the wines revealed that fermentations with individual and mixed Burgundian strains were more similar to one another than wines fermented with industrial strains. Calculation of odor active values (OAVs) allowed estimation of the sensory impact of each volatile compound. Radar diagrams of the OAVs revealed the estimated sensory profiles of the wine produced by industrial and Burgundian (individual, mixed) strains. The most distinguishing trait of the mixed novel Burgundian yeast strains was that they produced intermediate concentrations of most volatile compounds and that production of fruity aromas such as sweet fruit, strawberry, green apple, pear and banana were above the sensory threshold, while the production of nail polish, waxy, balsamic and vinegar were below the human perception threshold. The mixed culture of Burgundian yeast strains produced wines that were unique and more complex than wines produced with single industrial yeast strains. [Copyright &y& Elsevier]