What is Tannin?
Tannins, a group of bitter and astringent compounds, can be found abundantly in nature. Tannin is naturally found in plants, seeds, bark, wood, leaves, and fruit skins tea, walnut, cranberry, cacao and grapes. Perhaps most importantly, they’re also found in wine.
Tannin in wine comes from grape skins, grape seeds, oak or tannin powder.
Tannin in wine adds both bitterness and astringency, as well as complexity. It is most commonly found in red wine, although some white wines have tannin too.
Experiencing Tannin
Tannins are responsible for that astringent, mouth-coating feeling you get from biting into an unripe pear or plum.
I suggested why to experience tannin is to put a wet tea bag on your tongue. 50% of the dry weight of plant leaves are pure tannin. A less -not so direct approach- is to overbrew tea.
Other foods with tannin:
Tea Leaves, Grape Juice
Walnuts, Almonds, and other whole nuts (with skins)
Dark Chocolate, coffee
Cinnamon, Clove, and other whole spices
Pomegranates, Quince, Grape, and Açaí Berries
Experiencing Tannin in wine
In the mouth
While tannin is a collective term for various phenolic compounds, all tannins have one thing in common: they bind and precipitate proteins, i.e. separate them out. Human saliva is full of protein, which is what makes it so slippery. A tannic red wine will bind to saliva—this is what causes the mouth to feel dry.
Describing Tannin
Grippy used to describe when a wine has a pleasant amount of tannins, noticeable but doesn't dominate the wine
Green when tannins are described as “green,” they’re slightly bitter and have unpleasant astringency.
Polished” or “elegant -very fine-grained in texture, noticeable but balanced pleasantly in a wine’
Resolved tannins, which are smooth, soft and no longer astringent.
Wines to experience tannin
Red wines have more tannins than white wines, but not all red wines are equal. Here are some examples of high-tannin red wines:
Tannat: Uruguay’s most planted grape, Tannat is known for having some of the highest polyphenols of all red wines.
Sagrantino: A rare treasure of central Italy, Sagrantino stands neck and neck with Tannat with its extreme tannin content.
Petite Sirah: Originally French, Petite Sirah and its powerful flavors are now largely found in California.
Nebbiolo: One of Italy’s most legendary grapes, Nebbiolo boasts high tannin content and bitterness while still having a delicate nose.
Cabernet Sauvignon: You know this one. The most widely planted grape in the world is known for velvety tannins and high aging potential.
Petit Verdot: Known best as one of Bordeaux’s red blending grapes, Petit Verdot offers a floral, smooth sense of tannin.
Monastrell: Popular in Spain and France, Monastrell (aka Mourvèdre) has a smoky, bold sense of tannin.
Beyond variety
It’s helpful to remember that other things besides the grape variety greatly affects how much tannin is in a wine. Some things to consider
1. Climate
While grape variety can provide a good idea about the concentration of tannin in a wine, ripeness also matters. A good example is Syrah/Shiraz. It has a lot of tannin, but expresses itself differently, depending on climate and vintage. A hot climate like Barossa, Australia, produces Shiraz grapes that are superripe, making the tannins particularly smooth, lush and rounded. In the temperate Northern Rhône, the tannins come across as more structured, drying and angular. The tannin structure of Cabernet Sauvignon grapes from Bordeaux in France differ with warmer and cooler vintages
2. Winemaking styles
Maceration time, or the amount of time red wine spends in contact with its skins during winemaking, has an important influence. A shorter maceration allows less time for tannins and color. Rosé wines, for instance, have a short maceration time, which results in minimal color and little to no tannin.
Some winemakers also use grape stems to add structure to wines like Pinot Noir and Syrah. This means that the entire bunch goes into the fermenting vat. This is known as whole-bunch or whole-cluster fermentation.
Pigéage, or punch-down, is a very gentle extraction technique where the winemaker carefully pushes the grape skins that rise to the top during fermentation back into the must. Some wineries have tanks fitted with internal grids that keep the rising grape skins submerged.
Remontage, or pump-over, offers a slightly more effective extraction. The liquid at the bottom of the fermenting vat is drawn off and pumped back over the grape skins.
Délestage, or rack-and-return, is when a fermenting vat’s liquid is separated from the solids and poured back onto them in one motion. Some wineries also have so-called roto-fermenters, which are like giant front-loading washing machines that rotate. The movement helps extract both tannin and color.
3. Oak
Aging freshly fermented wine in new oak barrels will leach tannins from the wood into the wine. Good tannin management avoids harshness or bitterness, which happens when grapes are not sufficiently ripe or when over extracted.
Size matters
Large Barrels Will impart less flavor to the wine, because a lower percentage of liquid is in contact with the barrel’s wood. Small Barrels Will impart more flavor to the wine because a higher percentage of liquid is in contact with the barrel
The Type matter
The flavor imparted by an oak barrel is dependent on the method of preparation, the level of toast, and the type of wood.
• Types of Oak Different types of oak impart unique avors depending on the place of origin and climate in which the oak trees were grown
– American Oak Often has bold, more intense avors of vanilla, baking
spices, dill, and coconut
– French Oak Often subtler aromas of vanilla, toast, and spice
– Other Types of Oak Slavonian (from northeastern Croatia), Hungarian
• Toast Level
– Wine barrels are toasted on the inside during the coopering process to light, medium, or heavy levels, depending on the winemaker’s specification. Increased toast level increases the amount of vanillin, spice and toast flavors that can be imparted to the wine. Light toast promotes the most extraction of wood tannin.
Food and wine pairing: Lead with Tannin
The astringency of tannin is a perfect partner for rich, fatty foods. But you might be surprised at some pairings that delight. Try this activity below.
Foods that are sweet (from sugar, fruit or fruit juice, hoisin sauce, honey or the like) or high in umami (well aged beef, tomatoes, meat stocks or sauces) make any wine taste stronger/ more emphatic in its basic taste (sourness, bitterness or sweetness).
You can easily demonstrate this for yourself. Take a sip of your favorite Cabernet Sauvignon, then take a bite of apple, then try a sip of the wine again. The wine will taste more bitter as the sweetness in the apple makes the wine taste "stronger."
In contrast, sour components (vinegars, citrus, dry wine reductions) and salty components (including soy sauce, olives, olive brine) make wines taste milder fruitier, less acidic, less bitter. See for yourself: taste your Cabernet, then lick a wedge of lemon, and try your wine again. The wine fruit, acid and tannins taste more in balance.
Taste the Cabernet again, sprinkle a little salt on an apple slice, and try the wine again. Delicious. Unless you preferred that stronger taste resulting from the sweet apple, of course.
How the theory above impacts dishes
Chianti tastes better with a grilled beefsteak (red wine and umami, remember?) if it is served with a squeeze of lemon and a generous sprinkling of salt.
In Burgundy, a rich red wine will be served with rabbit (umami again) in either a vinegar or mustard sauce.
Pairing wine and steak
Tannin cuts through the intense meaty protein of a dry-aged fat-marbled steak, permitting subtler flavors of both wine and food to emerge. The tannin molecules actually bind onto proteins and other organic compounds in the food and scrape them from your tongue.
Rare versus Well-Done
Many red meat have high protein content which coats the mouth. Since tannin is softened by the interaction with protein, the young red wine will become smoother and refresh the palate. Young tannic red wines are an excellent choice for rare to medium rare red meats. Well-done red meats will have less protein and therefore work best with low tannin fruit-forward red wines.