Articolo disponibile anche in: Italian
As many of us know, September and October in Tuscany are dedicated to the wine harvest. Producers have to decide which is the right date to harvest the grapes, according to parameters which are only partially controllable.
The grapes of the vineyard mature according to their position, their exposition and altitude, to the structure and composition of the earth, to the trelling system, to the forcefulness of the rootstock, and, obviously, to the speciﬁc climactic conditions of the vintage. But the moment of the harvest is mostly dependent upon the vine: in similar conditions of those stated above, a Sangiovese will mature after a Merlot, but deﬁnitely before a Cabernet Sauvignon.
A few years ago, the wine producer exclusively trusted two main parameters to make his decision: sugars and, secondly, acidity of the grapes (the so-called ”technological maturity”, inducible with a refractometer or a saccharimeter).
These two references are still fundamental, but are helped today by a careful tasting of the grapes, fundamental in obtaining an excellent red wine: the consistency of the skin, the compliance of the color, the ﬂavors expressed by the grape, the level of harshness of the tannins, the degree of ligniﬁcation of the grape seed, indicate with additional certainty the stage of maturity of the grapes.
The maturation of the grape, in this case, is called “phenolic maturity”. For a vine like Sangiovese, unfortunately, it isn’t always easy to obtain, because technological maturity precedes phenolic maturity, and we risk the grape being overripe (too much sugar caused by the maturity of the tannins).
Wine operations, such as thinning (selection and limitation of bunches per plant before or immediately after veraison, in order to favor an optimal translocation of the tannins from the plant to the bunches), and deleaﬁng (this limits humidity, particularly risky during the harvest for a thinskinned vine like Sangiovese) are two fundamental factors in trying to synchronize these two moments.