Why Your Tongue Burns After Eating Sour Candy

The delights of sour candy can quickly become a siren call. The initial acidic tanginess followed by the saccharine sweet finish is an immensely satisfying flavor combo. There are a number of reasons why you might be craving this flavor rush. You could lack stomach acid in your body, be stressed out, or have a combination of these things (via My Complete Balance). Or you could just be a fanatic for that sweet-and-sour rush. 

Either way, anyone who's eaten tons of sour candy knows that there can be a consequence to all this mouth-puckering pleasure. In the best-case scenario, there's an intense burning sensation on your tongue, making your taste buds feel rough and raw. In the worst-case scenario, there can be tongue peeling — ouch! How can something that offers so much joy cause such physical pain? The answer lies in science. Or, more specifically, in the science behind the extremely acidic compound that is present in almost all sour candy: citric acid. 

The sting of citric acid

A naturally occurring compound in citrus fruit, citric acid can be concentrated and sold as a powerful powder and can often be found in the filmy dust that covers your favorite sour candy. Citric acid offers a flavorful boon to plenty of culinary projects, from adding the power of sour to your baking to bringing tangy oomph to your popcorn. This same chemical compound is the secret weapon of your favorite sour candy. 

Alas, while we crave its strong sour flavor, citric acid is highly corrosive, and it will begin quickly eating away at the papillae on your tongue.  As the citric acid is normally concentrated in the sour candy coating, it's the first thing our tongue touches and absorbs. Constant contact with this corrosive substance will eventually cause pain, as the nerve endings in our tongue send warning bells to our brain that we're beginning to eat away at our very flesh. 

So what should you do if you've rendered your mouth to sour-scorched earth? Take a break from the sour candy and give your tongue time to heal. Once things calm down again, you can return to sour candy; just be sure to drink plenty of water as well so that you can rinse away some of the citric acid afterward. You can also try following up your sour candy sessions with an acid-neutralizing glass of milk (per Food Network). Now that you know what causes the sour sting, you can better combat its corrosive qualities.