Tannins are an often-discussed topic when it comes to wine. You hear about how the bitterness in wine is due to tannins, and how you need to aerate wines to soften the tannins, and how you need to wait ten years for the tannins to subside in some wines. So the question becomes, WHY? Why do wines have tannins? Why do wines need tannins? Aside from the fact that tannins are antioxidants and an important contributor to the health benefits that wine provides, the answer, like the answer to many wine questions is both very simple and very complicated. Let’s take a look.
Tannins are Phenolic compounds that naturally occur in grapes. They probably developed as part of the fruits’ natural defense mechanism. As a fruit is growing, the bitterness makes it less appealing to would-be eaters. As it ripens, the tannins start to subside. Tannins are found in the skins, seeds and stems of grapes. As red wines (and we are talking primarily about reds when we discuss tannins) macerate during fermentation the tannins are absorbed into the wine. If the wine is aged in oak barrels, the oak will also add tannins to the wine.
The bite of tannins contributes to the balance of a wine, where the fruitiness, acidity, alcohol and tannins all play off one another. They also contribute to the mouthfeel and texture of a wine. In terms of taste we can think of tannins as a framework on which the components are built. The bitter backbone is countered by the fruit, livened by the acid and augmented by the alcohol. Without tannins, wine would taste overly juicy, sour and simple, and it would lack textural components. When wine is young the tannins are at their strongest.
There are four things that help eliminate the bitterness of tannins. They are:
• Fats
• Proteins
• Oxygen, and
• Time
Fats and proteins bond with tannins, lessening their bitterness. That’s one reason meat and cheese are good matches with young, red wine. Oxygen does something similar, bonding with tannins to make them taste less bitter. Aerators and decanters are helpful for this. But time is the most effective way to alleviate the bite of tannins in your wine. Over time, tannins bond together to form larger un-reactive molecules that are still perceptible as mouthfeel but they’re soft and supple, without their bitter bite. That’s why cellaring your wine is the best way to insure that you’ll always enjoy your wines to the fullest.
Care to talk about tannins further? Leave a comment, here!