Tannins in Wine

What are tannins in wine? You have probably heard about a wine being "tannic" or someone referring to a wine's tannins, but what does it really mean? In this guide you will learn about what tannins are, how they affect wine and examples of high and low tannin wines.

Dark red wine glass showin an example of high tannins in wine

Published April 14th 2020

Wines can be high or low in tannins and this affects the feeling and profile of the wine. Wine makers need to balance the wine's tannins in order for it to taste good. This guide gives you the answers to the most common questions about tannins in wine.

What are tannins?

Tannins are naturally occurring organic compounds that exist in grapes. In wine, tannins are the element that makes it feel dry. In addition to grapes, tannins exist in different plants, wood, leaves and fruits. They not only exist in wine and beverages, but also in food. The scientific word for the compounds that make tannins is polyphenols. In wine-making, tannins come from the grape skins, seeds and stems. They can also be added by the use of oak. Red wines contain more tannins than white wines. 

What do tannins taste like?

The best way to describe the taste of tannins is bitter and astringent. It makes the mouth dry when drinking the wine. Just like tannins in tea, tannins in wine have a drying effect. A tannic wine gives a similar feeling in the mouth as black tea. Tannins add a feeling to the wine, rather than a specific taste. You can determine whether a wine is high or low in tannins depending on how dry your mouth feels. If your mouth gets very dry, it is probably a tannic wine.

Are tannins important for wine?

Tannins are important to balance the wine. They can make the wine feel velvety, rich and complex. Tannins are often called the power of the wine. They give the wine texture and structure, which is often referred to as "body". If you like richer, full-bodied wines then you like tannic wines. Too high tannins can overpower the wine and it can make it overwhelming. They also give wine its beautiful color and makes it last longer. Tannins are one reason why red wines are often better to age than white wines.

Do tannins cause headaches?

Probably not, but since it is more common to get headaches from red wine than white wine, people are looking for differences between the wine styles. Since red wine is more tannic, it is sometimes speculated that tannins could be the cause. Other explanations for wine headaches are sulfites or histamines. Some studies show that tannins boost the production of the neurotransmitter serotonin in the brain. At high levels, serotonin can cause headaches for some people. Many are skeptical to this theory, and argue that if the problem is the tannin, these people should also get headaches from high tannic food such as chocolate, soy and black tea. Tannins might have some side effects for some people, but for the great majority of us, tannins create no headache or any bad feeling.

Do all wines have tannins?

No, not all wines have tannins. Tannins are mostly found in red wine and they usually come from fermenting the grape juice in contact with the grape skins, and from ageing in oak barrels. When white wine is made, the skins of the grapes are removed before the fermentation process. That is why white whine usually does not contain tannins. While tannins in red wine are more common, there are also tannins in white wine. Tannins can be added to white wines by aging in oak barrels. Oaked white wines are still less tannic than red wines. Young red wines often have grippy tannins and that is why you need to open the bottle or decant the wine before serving it. Letting the wine breathe before serving it will soften the tannins.

Which red wines have the most tannins?

Some types of wine and grape varieties have more tannins than others. Some grape varieties that are known for their high tannins are Cabernet Sauvignon, Syrah, Tannat, Touriga Nacional and Nebbiolo. All red wines have tannins, but full-bodied reds usually have a higher level than light-bodied styles such as Pinot Noir, Beaujolais and Barbera. Young red wines tend to be high-tannin wines and its a good idea to open the bottle and let the wine breathe for a while before serving it.

Which wines have low or no tannins? 

If you prefer low or tannin-free wines, you should choose a white wine. Most white and sparkling wines don't have any tannins. If the white wine is fermented in oak barrels it will have some tannins, although tannins in white wine are always lower than in red wine. Rosé wine usually has some tannins, but in low levels.