Tannins are essential to wine. If you’ve ever taken the time to learn about what goes into wine, then you may have that term before and how important they are to wine. If you’ve just started drinking wine, I urge you to take some time to learn about what you’re drinking. It will only help with wine selection, food pairings, and the overall wine-drinking experience. You may also understand why some people experience headaches from drinking red wine.
Tanning refers to the use of oak and other bark in tanning animal hides into leather. Let’s explore this a little further. Tanning hide into leather involves a process that permanently alters the protein structure of the skin. This makes it less susceptible to decomposition and more durable. Tanning compounds are found in a wide variety of plants, where they play a part in protecting from predation and might help regulate plant growth.
The astringency (an astringent is a chemical that shrinks or constricts blood vessels) from the tannins is what causes the dry and sour feeling in the mouth. You know the ones that make your lips pucker following the consumption of unripened fruit, red wine or tea.
In addition to their use in the process of producing leather, tannins are naturally occurring compounds that exist inside grape seeds, skins, and stems. The technical word for these compounds is polyphenols. Polyphenols release from the seeds, skins, and stems when they soak in the grape juice just after the grapes have been pressed. They give certain wines, such as Cabernet Sauvignon, their characteristic dryness or astringency. Any time you experience a drying sensation in your mouth after drinking wine- that’s tannins. You can determine whether a wine is low or high in tannins based on how dry your mouth feels. Tannic is the name for a wine that is high in tannins.
What makes a wine have weak or strong tannins depends on how long the juice sits with the grape seeds, skins, and stems after the grapes have been pressed. The longer the skins, seeds, and stems soak in the juice, the higher the count of tannins. This explains why red wines have stronger tannins than white wines since red wines soak longer. When producing red wine, the winemaker wants the skins to inject more color. The more color, the more tannins.
Tannins are also well-loved because they work as a natural antioxidant to protect the wine. This is one reason why certain red wines can be so age-worthy. After all, we know that antioxidants aren’t just great for aging wine but also have significant health benefits for humans.
Above, we mentioned headaches, which can be a potential downside to tannins. A good test is to eat something else that is strong in tannins such as a strong black tea or dark chocolate to see whether the same effect is obtained (see the note below to understand how to test for tannins). Although tannin headaches are rare, they can occur. If so, you may want to stick to white wines, which are low in tannins to avoid a tannin-triggered headache.
Note: brew a cup of extra strong black tea. Tannins occur naturally in black tea and their characteristics emerge when the tea is brewed a few minutes longer than recommended. After brewing the tea, take a sip and you’ll immediately notice a slight bitterness in the middle of your tongue and dryness in the front of your mouth — this is a tannin.