Influence of <i>L. thermotolerans</i> and <i>S. cerevisiae</i> Commercial Yeast Sequential Inoculation on Aroma Composition of Red Wines (Cv Trnjak, Babic, Blatina and Frankovka)

Abstract

Even though Saccharomyces cerevisiae starter cultures are still largely used nowadays, the non-Saccharomyces contribution is re-evaluated, showing positive enological characteristics. Among them, Lachancea thermotolerans is one of the key yeast species that are desired for their contribution to wine sensory characteristics. The main goal of this work was to explore the impact of L. thermotolerans commercial yeast strain used in sequential inoculation with S. cerevisiae commercial yeast on the main enological parameters and volatile aroma profile of Trnjak, Babić, Blatina, and Frankovka red wines and compare it with wines produced by the use of S. cerevisiae commercial yeast strain. In all sequential fermented wines, lactic acid concentrations were significantly higher, ranging from 0.20 mg/L in Trnjak up to 0.92 mg/L in Frankovka wines, while reducing alcohol levels from 0.1% v/v in Trnjak up to 0.9% v/v in Frankovka wines. Among volatile compounds, a significant increase of ethyl lactate and isobutyl acetate, geraniol, and geranyl acetate was detected in all wines made by use of L. thermotolerans. In Babić wines, the strongest influence of sequential fermentation was connected with higher total terpenes and total ester concentrations, while Trnjak sequentially fermented wines stood up with higher total aldehyde, volatile phenol, and total lactone concentrations. Control wines, regardless of variety, stood up with higher concentrations of total higher alcohols, especially isoamyl alcohol. The present work contributed to a better understanding of the fermentation possibilities of selected non-Saccharomyces strains in the overall red wine quality modeling.

Keywords

• <i>L. thermotolerans</i>
• volatile aroma compounds
• red grape varieties