The Grenache observatory was created in 1995. The object of this 24 parcels network, covering main Rhone Valley soils, is to state the effect of pedo-climatic conditions on plant physiology and wine characteristics. The results concerning colour and tanins show a very important diversity in Grenache behaviour. Anthocyanin content of grapes ranges from one to four, tanins from one to two. These important discrepancies are mainly quantitative and do not affect the thorough composition of grapes and wines. These results are confirmed in wines, and stable along the three years of this study. The parcels of the observatory can be divided in three groups, according to the phenolic content of their grapes. This grading is almost unchanged for the three vintages, which nevertheless were very different. Even if geo-pedologic conditions have an effect on wine phenolic content, climatic factors appear to be the most patent in this study.
Authors: G.MASSON (1), C. PUECH (1), L-M. BREMOND (2), F. BERUD (3), L. LURTON (1)
(1) Comité Interprofessionnel des Vins d’A.O.C. Côtes du Rhône et de la Vallée du Rhône
(2) Syndicat Général des Vignerons Réunis des Côtes du Rhône
(3) G.D.A. Viticulture, Chambre d’Agriculture du Vaucluse, Institut Rhodanien, 2260 route du Grès, 84100 Orange, France