Characterization of bunch compactness and identification of associated genes in a diverse collection of cultivars of Vitis vinifera L.

This work aimed to evaluate the evolution of phenolic compounds during white winemaking process up to bottling and 12 months storage, together with the influence of different antioxidant strategies

La maîtrise de la typicité du vin s’élabore au niveau local ou communal d’une exploitation viticole et/ou d’une cave, unité de vinification. La cave coopérative de Saint-Hilaire­-d’Ozilhan (AOC Côtes-du-Rhône), dont le territoire communal s’étend sur une superficie de 1 670 ha, couvre près de 310 ha cultivés en vigne. Elle réalise des vinifications «au terroir», en utilisant des regroupements d’unités de sol en 9 unités de terroir potentiellement viticoles, définies en s’appuyant sur la parenté des substrats. Diverses sélections d’une même unité peuvent aboutir aussi à des vins différents, ce qui suggère une hétérogénéité spatiale de certaines unités définies.

Nowadays, many policies are being adopted for direct agriculture towards more sustainable approaches. To continue to maintain a high production using fewer fertilizers, pesticides and water resources, agronomic techniques must be combined with biotechnological approaches. In grapevine, the breeding programs are restricted by the fact that it has a highly heterozygous genome, therefore, if on the one hand, we try to improve the characteristics, on the other hand it is necessary to preserve the original genome of the varieties. CRISPR-cas9 system is one of the smartest tools to carry out highly precise genetic modifications leaving the genetic background unchanged.

Among red wines ethyl esters, those from short hydroxylated and branched-chain aliphatic acids constitute a family with a particular behavior and sensory importance. They have been previously discussed in the literature [1] and recent studies have established that some of them were strongly involved in of red wines’ fruity aroma [2]. As some among them have an asymmetrical carbon atom, it seemed important to separate their different enantiomers to obtain an accurate assessment of their organoleptic impact. Three chiral esters have been identified, presenting alkyl and/or hydroxyle substituants: ethyl 2-hydroxy-4-methylpentanoate, ethyl 2-methylbutanoate, and ethyl 3-hydroxybutanoate.

Perceived aroma plays an important role in wine quality, and it depends mainly on the volatile composition. Volatile organic compounds (VOCs) from grapes and those formed during winemaking are involved in the sensory complexity of wines. In aroma-neutral winegrape varieties, the winemaking process itself, and particularly alcoholic fermentation (AF), impacts strongly on the organoleptic characteristics of wines due to the formation of volatile alcohols, acids, and esters. In addition, phenolic compounds could contribute not only to the wine color but also to VOCs evolution during AF.