Sweet wine of Negrar di Valpolicella for dessert and cheeses
The sweetness of a wine is given by the quantity of residual sugar. Residual sugars are those not fermented at the time of bottling. The sugars increase the sensation of body and sweetness of a wine, which becomes “sweet” when the residue is high. A “dry” wine can be defined as containing a residual sugar of about 4-5 g / l (grams per liter). As the residual sugars increase, it increases the smoothness of the wine. When the content reaches between 12 and 45 g / l, sweet wine can be defined as “sweet”.
Alcohol gives the wine a feeling of “warmth” and plays a complementary function to sweetness, contrasting with acidity. For this reason, some sweet wines are quite alcoholic, so as to be balanced and stable.
Sweet wines: production techniques
Residual sugars determine the sweetness of a wine. Alcohol is a derivative of the fermentation of must sugars. To obtain a sweet wine, however, it is necessary that only a part of the sugars be transformed into alcohol, while another part must be kept (part which corresponds precisely to the residual sugars). Since it is not possible to control fermentation, various techniques have been developed to produce sweet wines, through external interventions.
One of these, for example, involves the addition of concentrated musts, followed by filtration and stabilization with sulfur dioxide. The most natural method, however, is that which consists in starting from grapes containing the necessary and precise quantity of sugar.
Different from some red wines, as Corvina Veronese or Valpolicella Classico, in the passito the ripening of the grapes is intentionally prolonged and takes the name of late harvest. In this way, denser musts are obtained, with a higher sugar concentration per liter.
In fact, the passito wines are produced when the grapes are dried on the plants, or on special wooden racks. This is what happens, for example, for the Passito Veneto di Garganega, where the grapes are left to dry until January / February in dry and well ventilated rooms, with periodic checks on the health of the grapes, to avoid molding of the berries.
This technique allows to obtain a greater concentration of the juices, through the evaporation of the water contained inside the berries. It is the same technique also used to produce Recioto Della Valpolicella, an excellent dessert wine with a ruby red color with violet reflections.