This study examines the impact of IONYSWF yeast (Lallemand) on Chardonnay wine when compared to fermentation with CY3079. Chardonnay juice was settled and split into separate barrels, inoculated with either CY3079 or IONYSWF. Although the IONYSWF fermentation proceeded much slower, not many chemical differences could be seen between the different yeast strains, except that the pH and TA of the IONYSWF – fermented wine was slightly higher. The lower level of free sulfur dioxide in CY3079 suggests a slightly higher production of sulfur dioxide-binding compounds. These results suggest that people are able to tell a difference between Chardonnay wine produced with IONYSWF yeast and wine produced from CY3079. People often preferred wine produced with IONYSWF yeast, likely due to its tendency to enhance Fruit Intensity, Overall Aromatic Intensity, Depth of Flavor, and Body. Although the yeast is marketed to increase acidity, this was not observed in this study. This yeast shows promise with regard to aromatic development in Chardonnay, but more studies are needed to confirm this.
Andante, D254, and IONYS WF yeast strains were used in the fermentation of Petit Verdot. IONYS WF yeast seemed to increase the titratable acidity and lower the pH slightly, and also seemed to lower the overall phenolic content of the wine. IONYS WF and D254 wines were slightly more preferred than Andante wines.
Chardonnay was fermented with native yeast, WF, or CY3079 yeast strains. CY3079 produced higher volatile acidity, and was the least preferred yeast in sensory sessions. Native and WF yeasts showed similar chemistry and sensory preference.
The effect of ScottLabs IONYS WF and D21 yeast strains on Viognier chemistry and sensory characteristics were compared. The wine produced with D21 exhibited slightly lower pH, higher TA, and lower ethanol. Significant sensory differences were discerned between wines.