Ahh yes, wine. Glorious glorious wine. There's nothing like enjoying the subtle nuances of the Napa Valley, the bits of earthiness elevated by the notes of apple breath, all unifying in harmony in your two buck chuck as you delicately swirl it around in your Solo cup (hey, I'm not judging, that stuff is good).

coffee, chocolate, cereal, espresso, relish, candy
Christin Urso

But what about tannins? You've probably heard the word, usually associated with wines, teas, underripe fruits, and other bitter-ish foods and beverages, but what exactly are they?

sweet, banana, milk, cream, chocolate, candy, dairy product
Katherine Baker

Tannins are phenolic compounds (fancy words for chemical compounds) found in certain plants and algae that produce a dry, puckery mouthfeel, better known as the sensation of astringency.

coffee, cappuccino, espresso, milk, mocha, cream
Jocelyn Hsu

They were even used to dry animal hides into leather since prehistoric times. The process of drying produces a darkening color change to the hides, and the process of "tanning" leather has since given the compound it's name.

But for most of us, tannins are associated with their sensory impact in foods and beverages.

tea, herb, pepper, coffee
Prairie Broughton

The sensation of dryness you experience as the taster comes from the compound's phenolic shape: tannins consists of 3-5 rings that are just the right size to separate protein molecules.

When they hit the palate, they bond to proteins in saliva, and prevent them from doing their normal duty of keeping your mouth lubed up to make it easier to swallow your food.

pasture, grape, berry, gooseberry, vegetable
Jocelyn Hsu

 They leave the mouth feeling dry, and are found in red wines, certain teas, coffee, persimmons, pomegranates, berries, dark chocolate, grapes, and green bananas. They are nature's defense (or attempt at it) to keep animals from eating underripe fruit and plants, and have antibacterial and anti-fungal properties. 

wine, alcohol, sake, liquor, beer, champagne
Spoon University

While bitter and astringent, if balanced appropriately, tannins contribute to exciting sensory and flavor experiences in our dining experiences. Let's drink to that.