Contribution of Skin Contact and Yeast Selection to Aroma-Related Volatile Composition in Wines Made from New Fungus-Resistant Grapevines.

This study evaluated the impact of varying skin contact treatments and yeast strains on the volatile composition of wines from three fungal disease-resistant grapevine varieties (PIWI), aiming to optimize the extraction and formation of sensorially relevant volatiles during microvinification. 26 volatile compounds were quantitated in wines made from Calardis Soleil, Calardis Blanc, and Calardis Musqué, including polyfunctional thiols, monoterpenoids, and esters. Esters dominate in Calardis Soleil wines, while Calardis Blanc and Calardis Musqué exhibit more grape-derived aroma compounds. Skin fermentation and long maceration significantly enhanced monoterpenoid extraction in Calardis Blanc and Calardis Musqué. Yeast strains modulated ester formation and the release of polyfunctional thiols by up to 15-fold in Calardis Blanc wines for 4-methyl-sulfanyl-2-pentanone. Linking sensory data with volatile concentrations revealed how targeted enological measures can enhance the varietal expression of the three PIWI varieties under investigation and offer new perspectives to develop individual wine styles for new varieties efficiently.