Hanseniaspora in wine-making: their genetic modification and potential role in acid modulation

The physical factors that influence the grape ripening include elevation, slope, aspect, potential global radiation, sun hours and soil type of the vineyards.

Grapevines are continually wounded throughout their cultivation especially during winter pruning. Grapevines respond to wounding by occluding xylem vessels with gels or tyloses to limit pathogen attack and dehydration of the tissues. Although the production of xylem vessel occlusions has been studied in grapevine, to date we have no knowledge of whether different genotypes respond differently. The objective of this study was to characterize the genetic variation in xylem vessel occulsions in five different scion genotypes pruned at different dates.

Dans une approche globale, nous proposons la définition suivante du zonage : “représentation cartographique associée à une sectorisation du territoire en zones unitaires homogènes à partir de facteurs discriminants établis sur la base d’indicateurs quantifiables et d’avis d’experts”. La première application de cette méthode a porté sur la caractérisation du terroir en liaison avec les aspects qualitatifs des vins. Il est également possible d’envisager d’appliquer cette démarche dans les stratégies environnementales et paysagères liées aux approches territoriales et aux pratiques viticoles. Cette méthode peut servir de base dans la mise en œuvre des outils financiers associés aux mesures environnementales (CTE, aides spécifiques).

The quality of a wine is largely related to the balance between its sourness, bitterness and sweetness. Recently, molecules coming from grapes have been showed to notably contribute to sweet taste of dry wines. To study the viticultural and oenological parameters likely to affect their concentration, their quantification appears of high interest and subsequently requires powerful analytical techniques. Therefore, a new method using liquid chromatography coupled to high resolution mass spectrometry (LC-HRMS) was developed and validated to quantify epi-DPA-3′-O-β-glucopyranoside acid (epi-DPA-G) and astilbin, sweet molecules identified in wine. Three gradients were tested on five different C18 columns (Hypersil Gold, HSS T3, BEH, Syncronis and Kinetex).

The ambition of the zonation of the Doc “Sangiovese di Romagna” is described as 25 siti sperimentali, aventi diversa origine geologica, in cui è stato individuato un vigneto omogeneo per la determinazione dei principali parametri viticoli ed enologici. In seguito è stato analizzato il contentto di stilbeni nei vini al fine di indepth il legame con le charatteristiche geopedologiche. The studio describes the positive relationship between the altitude and the content of the trans -piceide nelle province di Forlì and Ravenna and of the trans -resveratrolo a Ravenna. I suoli con maggiore calcare attivo hanno fornito vini più ricchi in stilbeni.