Xylem vessel blockages in grape pedicel growing in tropical climate observed by microtomography

L’économie cidricole française est concentrée dans les régions du grand Ouest avec environ 40% de la production nationale de pommes à cidre pour la seule région Bas-Normande où le Pays d’Auge occupe

The evaluation of different chemical compounds present in Uvalino wines was correlated with sensory analysis. The analysis showed a high content of polyphenolic compounds responsible for the organoleptic properties of wine, including color, astringency and bitterness.

The use of stems during fermentation is generally avoided due to the herbaceous off-odors they can impart to the wine. [1].

Anthocyanin potential of grape berries is an important quality factor in wine production. Anthocyanin concentration and profile differ among varieties but it also depends on the environmental conditions, which are expected to be greatly modified by climate change in the future. These modifications may significantly modify the biochemical composition of berries at harvest, and thus wine typicity. Among the diverse approaches proposed to reduce the potential negative effects that climate change may have on grape quality, genetic diversity among clones can represent a source of potential candidates to select better adapted plant material for future climatic conditions. The effects of individual and combined factors associated to climate change (increase of temperature, rise of air CO2 concentration and water deficit) on the anthocyanin profile of different clones of Tempranillo that differ in the length of their reproductive cycle were studied. The aim was to highlight those clones more adapted to maintain specific Tempranillo typicity in the future. Fruit-bearing cuttings were grown in controlled conditions under two temperatures (ambient temperature versus ambient temperature + 4ºC), two CO2 levels (400 ppm versus 700 ppm) and two water regimes (well-watered versus water deficit), both in combination or independently, in order to simulate future climate change scenarios. Elevated temperature increased anthocyanin acylation, whereas elevated CO2 and water deficit favoured the accumulation of malvidin derivatives, as well as the acylation and tri-hydroxylation level of anthocyanins. Although the changes in anthocyanin profile observed followed a common pattern among clones, such impact of environmental conditions was especially noticeable in one of the most widely distributed Tempranillo clones, the accession RJ43.

Les composés actifs du vin ont, jusqu’ici, peu fait l’objet d’études sur le temps long. Le développement de l’œnologie, de l’analyse des vins et, de manière concomitante, l’essor des règlementations vinicoles au XXe siècle révèlent pourtant au grand jour le poids de ces composés et leurs évolutions. Dans cette communication, nous souhaitons montrer comment l’acidité volatile des vins,