Polyphenols in kombucha: impact of infusion time on extraction and investigation of their behavior during “fermentation”

The use of high-power ultrasound (US) during the winemaking process has been extensively studied at laboratory scale in order to demonstrate its possible use to improve the extraction of compounds of interest. However, studies on semi-industrial and industrial scale are needed to confirm this positive effect, since the International Organization of Vine and Wine approved its industrial use in 2019 [1].

Climate change (CC) is altering grape/wine composition, leading to challenges in maintaining wine sensory quality.

Trebbiano di Lugana (TdL) is a white variety of Vitis vinifera mainly cultivated in an Italian area located south near Garda lake (Verona, north of Italy). This grape cultivar, also known as “Turbiana,” is used for the production of TdL wine with recognized Protected Designation of Origin whose volatile profile was recently determined [1]. The presence of varietal thiols in TdL, namely 3-mercaptohexan-1-ol and its acetate form, conferring the tropical and citrus notes, has been documented. Winemaking strategies were also described with the purpose of protecting and maintain these desired aromas [2]. To the best of our knowledge, the varietal thiol precursors (VTPs) were not previously determined in TdL grape and must. This study aimed to quantify VTPs in both grape during the ripening and must during the pressing. Volatile C6 compounds were also measured in the must fractions.

AIM: Glutathione (GSH) is a powerful natural antioxidant, considered as a promising molecule against oxidative damage of aroma during winemaking and storage.

Climate change has led to increased extreme weather events, such as severe droughts and intense rainfall, with regions like Alentejo and Algarve in Portugal, being particularly affected.