What are wine tannins?

By definition, tannins are: Any large polyphenolic compound containing sufficient hydroxyls and other suitable groups (such as carboxyls) to form strong complexes with various macromolecules.

Uhh…with such a technical make up, it seems that you wouldn’t find this in some foods and wine. But it’s there…lurking in the corners. You’ll find tannins in things like coffee, tea, whole nuts and even dark chocolate.

In the wine world, tannins help create structure, balance and age-ability in red wines. Ever feel like you need a glass of water after drinking certain red wines? That is tannin drying your mouth out.

To have a better understanding of tannins, we have to jump into wine production a bit.

However, you won’t find these guys in white wines.  For white wine production, green grapes, like Sauvignon Blanc or Chardonnay, are brought into the winery and pressed for their juice.  That juice is then fermented and turned into wine, more or less. There isn’t any contact with the grape skin, stems or seeds – so, therefore, no tannins since those are the three components that produce tannins.

Red wines go through a different process. Instead of pressing the grapes, they are smashed up or run through a crusher. I think most of us, of a certain age, remember the “I Love Lucy” episode where Lucy and Ethel are dancing around on wine grapes, having fun. Well, it’s not quite like that, but you get the idea.

The final product, before fermentation, is juice, skins and seeds – or the “must”.  This is then fermented for 7 – 10 days. During that period, the clear grape juice (yes, red grapes bleed white juice) starts to extract color and flavor from the skins. It is also extracting tannic acid from the skin and seeds. Sometimes, winemakers will include the stems, as well, to add some grassy or green bell pepper notes to a wine. The stems will also introduce tannic acid. Ultimately this will develop the full tannin structure of the wine.

One thing that is important to note: the tannic acid level is not the same for all red wines.

Acid in wine is determined by the grape skin thickness. So, a thin skinned grape (think Pinot Noir) will have less tannic acid than a thick skinned grape (think Cabernet Sauvignon).

At this point the wine has too much tannin to be bottled. It is so strong that it overpowers all of the great fruit in the wine.

To get that reduced, winemakers will put a quality red wine through an oak barrel aging process. That oak barrel allows oxygen to slowly penetrate into the wine, reducing the tannic acid and revealing the other flavors.

What the winemaker is trying to achieve is a balance of fruit, acid and oak. Creating a wine with “drinkability”. There are multiple factors, winemaking styles and philosophies involved in attaining balance in wine and it is defined by each individual winemaker. The subject of “how to achieve balance in wine” can take up a whole website, for sure.

Wines that are mass produced go through a slightly different process. Winemakers pump oxygen directly into the wine to reduce acid.  This is a process known as micro-oxygenation. This is supposed to take the place of barrel aging a wine over time. It is a very cheap way to try and get the same result. That is why many mass produced/inexpensive wines are high in tannins.

As is the case with a lot of shortcuts in life, this shorter, less expensive method doesn’t quite achieve the same result.  The barrel aging process is a tried and true way to balance a wine. For a quality producer, there is no short cut for this process.

With so many different wines out there, how can you tell if it’s a soft, medium or heavy tannin wine?

It’s not easy, especially if you are new to wine. Knowing your red wine grapes is a big plus. The two extremes of Pinot Noir (thin skin) and Cabernet Sauvignon (thick skin) are easy. The hundreds of other varietals in between, not so much.

Tannin level in wine gives you the “weight” or “mouth feel” of the wine. Tannin levels are different for every drinker, but grapes can be categorized as are soft, medium or heavy on the tannin scale. You often see “soft or light”, “strong or heavy” as tannin descriptors. This also correlates to the bitterness factor of a red wine.

On your palate, the first taste of a strong tannin wine is bitterness. The acid wasn’t reduced enough in the aging process and the bitterness didn’t soften enough. It’s a little harder to pick out the fruit and other flavors of the wine when the bitterness is so powerful. Some examples of strong tannin wine would be: Cabernet Sauvignon, Malbec, Mouvedre and Zinfandel.

A medium tannin wine will have the bitterness effect in the middle of the palate. It’s not so strong that it will hit you right away, but is in the beginning of the finish. Good examples of medium tannin wines: Shiraz, Merlot, Cabernet Franc and Barbera.

A soft tannin wine will have a slight bitterness more on the finish with the fruit being more forward. Examples of light bodied wines: Pinot Noir, Sangiovese, Grenache and Cargignan.

Now that you’ve got the wine part figured out, what’s for dinner?  Food pairings are always fun, when it comes to red wines. The sweet spot for food and red wine would be the medium bodied reds.

You name it and you could probably pair a medium tannic red with it.  Yes, even (gasp) fish.  The list continues with BBQ ribs, burgers, roasted chicken, pizza, salmon, swordfish, crusted mahi.

Feel like a light meal?  Soft tannin wines are great with lighter fare. A nice pasta in olive oil, chicken Caesar salad or grilled shrimp with grilled fruits. These wines can also drink well on their own, a “cocktail” wine, if you will.

As you probably guessed, the heavy wines go with bolder foods, a rich tomato pasta, steak and potatoes or a beef bourguignon (which includes a bottle of red in the recipe!).

One thing to remember, the stronger tannin wines have a little thing called “age-ability”. Tannic acid helps a wine with its shelf life. If you have a bottle that has a little too much tannin for your taste, you could continue the aging process by storing the bottle away for a few years. With the proper storage conditions, the acid will continue to reduce until balance has been achieved.

There’s no secret to figuring out your personal tannin tolerance. Experimentation is the best way.  Sure, it may take a case of different wines to do it…but that’s half the fun.

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