Think Tannins: How Tannins Affect Red Wine

Even the most neophyte of wine drinkers have heard about tannins. Most of us have an idea of its effects on the wine’s texture and mouthfeel.Critics use words like ‘grippy,’ ‘rigid,’ ‘round,’ ‘muscular,’ ‘voluptuous,’ and ‘spineless’ to describe a wine’s tannin content. But what exactly are tannins and how do they shape the overall structure of your wine cellar favorites?

What exactly are Tannins?

The word tannin figures heavily in history, not just for its use in wine, but for its myriad of other practical applications. It’s found primarily in seeds, wood, bark, leaves, plants, and fruit skins and this natural polyphenol is used to connect various chemical properties. In the consumer goods industry, plant tannins are used in the process of curing leather. Hence, the term ‘leather tanning.’ Animal skin starts out rather soft and floppy. But by using plant tannins to bind proteins, the skin toughens to a degree where it could be fashioned into belts, shoes, saddles, bags, and other leather products.

Now, in the wine industry, tannins have a whole different presence and purpose. The polyphenol is found in the wine grape’s pips (seeds), stems, and skins. It’s used to impart color, flavor, texture, and mouthfeel to the vino. Red wines tend to have more prolonged contact with the grapes’ seeds, stems, and skins, which is why these crimson wines have more concentrated tannin content compared to their white counterparts.

How Do Tannins Affect the Taste, ‘Feel,’ and Aging Potential of Red Wine?

Besides grapes, tannins can be found in a wide variety of food. It’s present in nuts, tea leaves, dark chocolate, pomegranates, cloves and even red beans. Tannins are crucial in the way these staples taste and ‘feel.’ For instance, notice how tea tends to be bitter and astringent. It also seems to have a drying effect on both the tongue and the palate. These are the same qualities tannins impart to wine.

For example, a tannic red wine will taste rather strong and it could come off as unpleasant to the novice wine drinker. Its astringency can be felt on the front and back of the mouth. If a wine’s tannin content is particularly high, then the polyphenols can be sensed even on the gums and the insides of the cheeks. This ‘feel’ is an acquired taste for red wine lovers, and is the one of the many reasons tannins are good for wines.

See, in nature, tannin is thought to be a form of plant defense. The astringency is designed to deter insects and animals from feeding on the hapless plant. In its purest and most concentrated form, wine tannins can also deter the most determined of drinkers. This is why winemakers are careful when it comes to controlling the amount of tannins penetrating the tipple.

When used properly, tannins can help enrich the wine’s color, flavor profile, and mouthfeel. Because these polyphenols are also natural antioxidants, they arrest early oxidation which helps the vino’s bottle aging potential. This is one of the reasons varietals that are high in tannins like Cabernet Sauvignon, Nebbiolo, Petite Verdot, Montepulciano, and Tempranillo figure high in the list of ‘cellar-worthy’ wines.

To understand the difference between tannin-heavy and low tannin wines, we recommend doing a side-by-side sampling of Cabernet Sauvignon and Pinot Noir. The latter—along with Merlot, Grenache, and Zinfandel—has less tannins than other reds. Hence, the Pinot’s lighter and sometimes reedier structure.

Telling Tannins from Acidity

This is a point of confusion (and sometimes contention) for many red wine drinkers. Because reds have both acidity and tannin content, it can be tricky to pinpoint what you’re tasting. Is the wine astringent or is it highly acidic? Well, here’s a simple trick you can use if ever you’re invited to a wine tasting event.

To tell tannins from acidity, consider the wine’s ‘finish’ and ‘mouthfeel.’ If after swallowing the liquid, you find yourself salivating, then what you’re sensing is acidity. As we mentioned earlier, tannins will leave a dry taste or feel in your mouth.

Health Benefits of Tannins

Red wine is good for the heart and it’s the resveratrol that’s in the wine that helps. This type of natural phenol has long been regarded as the main cardiovascular helper in wine. But some scientists believe that the key to good heart health actually lies in tannins. According to University of Glasgow biochemist, Alan Crozier, the amount of resveratrol in wine is too small to impact your health. Crozier said that while resveratrol has boosted the cardiovascular health of animals during experiments, one will need to drink about 1,000 liters of wine each night to attain the same results.

You won’t have to drink that much to get the benefits of resveratrol in your system. In fact, we strongly recommend that you limit your consumption to one or two glasses per night (or day if your prefer). You can get the benefits of red wine through drink’s oligomeric procyanidins (a.k.a. concentrated tannins). These flavonoids can reduce the buildup of peptide, which is what hardens the arteries. Now, that’s good news we can all drink to.