Whether you’ve been drinking with snobs or not, chances are you’ve heard the word tannin bandied about in wine circles. So for today’s post, I thought I’d keep it simple with a quick explanation of what exactly tannins are and what they do.
Tannins are chemical compounds (polyphenols, to be exact) found in grape skins, seeds and stems. They can also come from oak barrels in which wines are aged. These compounds are released while they soak in the grape juice after pressing, so you’re going to find more of them in red wines than white since red wines sit on the skins for a time during fermentation.
Certain grape varieties are more tannic than others. For instance, Nebbiolo and Petit Verdot generally have more tannins than varieties like Grenache or Pinot Noir. Wines with lots of tannins can be bitter (some might call them astringent) and make you feel like your mouth is drying out and your tongue is dusty, sort of like over-brewed tea or coffee. That’s because polyphenols tend to latch onto proteins like the ones in your saliva and reduce their lubricity. Thus the dry mouth. And yes, lubricity is a word.
But if all they do is make you pucker up, why not try to get rid of them altogether? There are a few reasons for that. First, with red wines, that juice needs to sit on the skins in order to take on a nice color, so you’re stuck for that bit. Beyond just coloring, tannins also impart complexity to a wine. Tannins can taste sawdusty, true, but they can also be described as velvety or silky or plush, depending on the wine, so they can heighten the pleasure of the wine’s taste.
Tannins protect plants from environmental stresses because they’re natural antioxidants, so they also prevent wine from spoiling due to oxidation. They can give some wines the ability to age for years or even decades. Wines that age for a long time often have gentler tannins than new wines, and some scientists think that’s because they tend to “mellow” by binding to the pigment particles in wine and settling out of the liquid (they may be part of the sediments that settle on the bottom of that bottle), though the science on this is inconclusive.
Back to that bitter taste, though. If you open a bottle of wine or order a glass only to find that it’s making you pucker up like a politician kissing babies on election day, just give the wine a little extra time to breathe. You can use an aerator, or simply swirl it around in your glass for a while. The oxygen you introduce will start breaking the tannins down and bringing out the subtler nuances of the wine.
Some people also blame tannins for those wine headaches, but they’re not usually the culprit. If you don’t get a headache from drinking over-extracted tea or eating walnuts or dark chocolate, chances are it’s not the tannins bothering you.
If making wine is like putting together a beautiful piece of furniture, I think of tannins like the sandpaper. Sure, they can seem rough and abrasive at first, but if you put them to good use, they can help you make a finely polished, refined, beautiful product meant to last for ages. Think about that the next time you pucker up!