Tannins in Wine
You know that pleasant sensation of astringency that a good red wine arises while “touching” the palate and that highlights its “character”? This effect is due to the tannins in the wine, which play a fundamental role in defining its taste and typical color.
You would have heard a sommelier while describing the virtues of a tasteful red wine: a real sensory journey that involves the scent, appearance, texture and that defines the taste in every detail.
Sommeliers and enthusiasts often speak of tannins and sometimes use the expression “tannic wine” to indicate those wines particularly astringent and suitable to be combined with dishes elaborated as roasted or boiled.
But why does wine contain tannins? Thanks to its raw material, grapes, that like all the plants contains them naturally, but also thanks to the wooden barrels in which the wine is aged. Both of these comprise of a certain amount of tannins, like all the members of the plant kingdom. The combination of these two factors generates a unique, scented wine.
From the Plant to the Barrel: the Journey of Tannin
Tannins are polyphenols, naturally present in all plants and fruits, and therefore also in grapes (Vitis vinifera). In particular, they are contained in the grape seeds and in grape skins.
The red wine is obtained by leaving the mash to ferment together with the grape seeds and peels, which gradually release the tannins in the must during the process of maceration and fermentation.
It is always the tannin that imparts to the wine its typical color: a warm red, in different shades, depending on the type of grapes used and the time of aging.
It does not happen in white wines, since their process making generally does not include maceration, and consequently there is no contact between must and pomace. The rosé wines making process includes a short maceration, from few hours to 1-2 days
From the Barrel to the Glass: the Key Role of Wood
Grape tannins are not the only ones that play a key role. In fact wine ages in wooden barrels, usually Oak (especially durmast and farnia) or Chestnut. Both contain high concentrations of tannins.
In contact with the must, the wood of the inner part of the barrel releases its tannins, contributing decisively to the definition of the final taste.
When you read “Aged in oak barrels” you will know that the Oak tannin deserves the credit for the amazing taste of your wine.
The wooden barrel also has another virtue: it helps avoiding the leak of liquids while allowing a light and constant oxygenation that, together with the action of the tannins in wood, contributes to give the wine a more balanced aroma and an intense color.
Wine Tannin: some Interesting Details
Variable Quantity
The quantity of tannins contained in wine can vary according to different factors, such as the type of grapes used, the type of wood of the barrels, the environment where the wine ages and the relative conditions of temperature and humidity.
Time, a Key Factor
Of all the variables, the decisive one is the aging time of the wine. In young wines, tannins have shorter molecules, which confer an astringent and “aggressive” flavor. With time, they tend to polymerize, for a more “round” and velvety taste.
Matching Food and Wine
Tannic wines are generally combined with succulent dishes, both because they help to digest fats and because the astringent sensation in the mouth prepares the taste buds to transpose the next bite into the best.
Some Examples
Some wines naturally contain more tannin than others and this strongly influences the final result. Malbec, Cabernet Sauvignon and Syrah are rich in tannin; on the contrary, Pinot Noir is low in tannin.
Tannin and the Sommelier
Sommeliers pay great attention to tannin while selecting and tasting a wine.
The official courses and masterclass organized by the Worldwide Sommelier Association always include detailed studies about tannins in wine: understanding and recognizing tannins is considered a fundamental step towards wine connoisseurship.
There are also real classifications based on wine tannins, like the one provided by the Italian Sommelier Association. According to this classification, a wine can fall in 5 different categories according to the sensations arising by the presence of tannin, like dryness, astringency and roughness.
Find out More About Tannin
The production of wine involves the tannin naturally present in the grapes and the wood of the barrels. In addition to wine making, tannin can be used in many other areas: in vegetable tanning, animal feed, nutraceuticals and even cosmetics. Go to Applications page and learn more about how tannins can be used industrially.