What are tannins?

(that is to say, complex bonds of oxygen and hydrogen molecules) that play an important role in wine, determining, for example, the colour of a given wine. Among the polyphenols present in wine, we find tannin itself, alongside phenolic acids, flavonols and anthocyanins (of the flavonoid family) and resveratrol.

Tannin adds to wine a bitter sensation of astringency, as well as structure and complexity. It is commonly said that “it dries the mouth“; to put it another way, it is the same sensation of “dryness” you experience when you bite into a quince. It is found most commonly in red wine, although some white wines also have tannin (from ageing in wooden barrels or from fermentation on the skins). In general, we can say that the higher the amount of tannin in a wine, the more acute the sensation of astringency on the palate.

As mentioned previously, tannin is an organic and natural substance present throughout the plant world: in plants, in leaves, in seeds, in wood and in the skin of fruit. In a grape bunch, tannin is found in the stem, in the pedicel, in the pips and in the skins. It is extracted during the maceration phase, varying according to the acidity of the wine. In young wines, tannins are present in simple molecules, rather aggressive and astringent, whilst with ageing, such compounds become more complex, rendering wines more evolved, that is less astringent and softer.
Let us remember that, in addition to the tannins naturally contained in the grape, these compounds are also found in wood, so during the maturation phase the wine acquires others during its time in barrel or barrique. Wood releases, in fact, additional tannins that contribute to adding astringency and aroma to the wine. The smaller the barrel, the better the exchange of aromatic substances: this is where the saying “in the small barrel lies good wine” comes from.

Among the best examples of tannic red wines from Cantine Leonardo da Vinci, we find many labels. To name a few, we suggest tasting Rocca di Cesena Sangiovese Superiore Riserva Romagna DOC from the 1502 Da Vinci in Romagna line; Vergine delle Rocce Chianti Riserva DOCG from the Da Vinci I Capolavori line, or also the San Giovanni Battista Brunello di Montalcino DOCG.

Tannin is one of the key traits that allows red wines to age well for decades. Over time, complex tannin molecules polymerise, smoothing and softening that sense of astringency typical of young tannins. This is one of the main reasons why a young and powerful wine such as Brunello di Montalcino is often aged for up to 10 years before being opened.
In enology, this type of tannin released by wood into the wine is technically called “gallic tannins” and has less capacity for astringency than “endogenous” ones extracted directly from the grape, and for this difference they are defined as “sweet tannins” or “noble tannins”.