Etude des effets millésime, situation et sol à partir d’un observatoire du Gamay en beaujolais

The professional winegrower usually selects the harvest date considering several elements, such as the vine stem and berry colour, the flavour, appearance and grain elasticity. Nowadays these elements have turned old fashioned.

Yeasts serve as highly versatile tools in oenology. They do more than just perform alcoholic fermentation. Nowadays, yeasts from various species, naturally present in grapes, are selected for specific non-fermentative applications. For example, the use of selected non-saccharomyces at the early stage of winemaking has become a common practice to limit the growth of unwanted microorganisms. When inactivated, yeasts can be fractionated into soluble and insoluble fractions providing a wide range of benefits related to structural components or specific metabolites.

Hydroxytyrosol (HT) is a phenolic compound present in olives, virgin olive oil and wine. HT has attracted great scientific interest due to its biological activities which have been related with the ortho-dihydroxy conformation in the aromatic ring. In white and red wines, HT has been detected at concentrations ranging from 0.28 to 9.6 mg/L and its occurrence has been closely related with yeast metabolism of aromatic amino acids by Ehrlich pathway during alcoholic fermentation. One of the most promising properties of this compound is the neuroprotective activity against pathological mechanisms related with neurode-generative disorders including Alzheimer’s and Parkinson’s disease.

Astringency is a crucial sensory attribute typically described as the drying and/or puckering sensation occurring after the consumption of tannin-rich foods and beverages. In this study, thirty-seven red wines from different varieties, origins and styles were evaluated, analyzing both chemical and sensory features. Principal Component Analysis was used for dimensionality-reduction and for correlating selected chemical parameters against astringency. The results showed that tannin content was the most important chemical parameter influencing overall astringency but more clearly the dryness sub-quality, followed by pH, titratable acidity and alcohol content.

La découverte d’une vigne gallo-romaine en plaine à Gevrey-Chambertin (Côte-d’Or) constitue un point important pour la compréhension de la construction des terroirs viticoles de Bourgogne. Sa situation en plaine constitue pour nous le point de départ d’une large réflexion sur la mise en place du modèle de viticulture de coteau qui prévaut en Bourgogne et sur les facteurs de ce changement de norme de qualité viticole. Les sources mobilisées pour cette approche interdisciplinaire et diachronique sont géomorphologiques, archéologiques et textuelles.