LAUSR

This study shows the impact of three different commercial inactive yeast derivatives (IYDs) (Opti Less™, Noblesse™, Optimum White™, Lallemand, Canada and Oenolees MP™ Lafort, USA) during the 6-month aging period on the volatile profile, sensory attributes and antiradical activity, including polyphenols and the total free sulfhydryl (-SH groups) content, of Grašac wines made in sequential fermentation with native Hanseniaspora uvarum S-2 and Saccharomyces cerevisiae QA23. The addition of IYDs helped in maintaining the constant values of antiradical activity during aging by increasing polyphenolic values and mitigating the decrease in -SH groups. HS-SPME-GC-MS analysis showed that esters were the major volatile compounds, with ethyl-acetate and 2-phenyl-ethyl-acetate being the most abundant among all the samples, followed by ethyl-dodecaonate, ethyl-decanoate and 3-methyl-butyl-octanoate, all of them contributing to fruity and floral aromas in wine. As the concentration of IYDs increased, a corresponding rise in the levels of certain volatiles, such as 2-methyl-1-propanol, phenyl-ethyl-alcohol and ethyl-octanoate, was observed. Sensory analysis showed that the addition of IYDs generally improved the taste and odor profile of the wine by reducing astringency and increasing fullness and complexity, regardless of the IYD type. The results demonstrated that different IYDs may have varying effects on wine, with each product having its specific purposes, providing the tools for winemakers to carefully regulate and obtain the desired sensory profile of the wine.