Observatoire Grenache en Vallée du Rhône: incidence du terroir sur certains précurseurs d’arômes et substances volatiles

OTA occurrence in wine is well-documented, with higher levels typically found in red (< 0.01-7.63 μg/l), followed by rose (0.01-2.40 μg/l) and white wine (<0.01-1.72 μg/l). Incidence rates are nOTAble, with studies showing OTA present in 53% of 521 red wines, 69% of 98 rose, and 61% of 301 white wines analysed. In europe, wine is estimated to be the second source of OTA intake after cereals. Since 2006, the maximum allowable limit for OTA in wine is 2 μg/l, according to regulation (ec) no. 1881/2006.

Anthocyanins and tannins contribute to important sensorial traits of red wines, such as color and mouthfeel attributes.

The mechanisms behind thiol precursor accumulation in grapes remain incompletely understood, nor are the ways in which they can be improved by agronomic practices. A six-year field trial studied the physiological response of the Swiss white cultivar Vitis vinifera Arvine, rich in varietal thiols and precursors, to canopy management, i.e. leaf removal and canopy height.. Five treatments were set up in a randomized block design to assess the impacts of 1) pre-flowering LR (i.e. pre-flowering or full-flowering stages) and 2) compensating for the leaf area removed in the cluster zone by increasing the trimming height (i.e. 100 or 150 cm canopy height), compared with a non-defoliated control treatment.
Intensive pre-flowering LR severely reduced yield potential (–47% on average) and reduced the concentration of 3-mercaptohexanol precursors (P-3MH) in the must (–21%; p-value < 0.10).

DNA-binding proteins play a pivotal role in critical cellular processes such as DNA replication, transcription, recombination, repair, and other essential activities. Consequently, investigating the interactions between DNA and proteins is of paramount importance to gain insights into these fundamental cellular mechanisms. Several methodologies have been devised to uncover DNA-protein interactions, which can be broadly categorized into two approaches. The “protein-centered” approach focuses on identifying the DNA sequences bound by a specific transcription factor or a set of TFs. Techniques falling within this category include chromatin immunoprecipitation, and protein-binding microarrays.

The postharvest dehydration of grapes is a traditional practice to obtain wines with unique traits (e.g., sweet, dry/reinforced).