Identifying research opportunities at Douro Demarcated Region

Climate is one of the main components that defines the development and behavior of the plant, conditioning the health status and the final quality of the grapes. In temperate coastal climates such as in Uruguay (latitude 35° S, longitude 55° O), precipitations during the growing season present high interannual variability, with a average of 100 mm per month. This variability means that plants must adapt to conditions from one year to the next.

The aim of the project was to characterize the Premium Denomination of Guaranteed Origin (DOCG) “Colline Teramane” wine-growing region and to delineate and define homogeneous zones (terroir units) within it, by applying a multivariate clustering approach combined with geomatics.

Varietal Riesling aroma relies strongly on the formation and liberation of bound aroma compounds. Floral monoterpenes, green C6-alcohols, fruity C13-norisoprenoids and spicy volatile phenols are predominantly bound to disaccharides, which are produced and stored in the grape berry during berry maturation.

Rotundone is the main aroma compound responsible for peppery notes in red wine. This positive and very potent molecule has an odor threshold of 8 ng/L in water and 16 ng/L in red wine. It has been detected in several grape varieties with some of the highest concentrations recorded in Syrah, Duras, Tardif and Noiret, an interspecific hybrid grown in the North-East of the USA. If several winemaking practices have been identified to lower rotundone in wine, up to date, no enological solution has proved its efficiency to maximize it. This means that efforts to produce high rotundone wines must be undertaken in vineyards. This work provides practical ways that can be used by winegrowers to modulate rotundone levels in their wines.

Foreseeing climatic changes, the abnormally hot and dry year of 2005 can be revealer of some varieties behavior in different climatic conditions.