Whether a tomato sauce or a cup of black coffee, acidic food and drink can elicit many different reactions from an individual's palate. For most, acidic foods cause a sensation on the tongue known as "brightness" -- a tingling, numbing reaction. This is especially true in the case of black coffee. However, others may experience more unpleasant reactions to acidic foods, such as a prolonged stinging, numbness or even the development of irritating mouth sores.
The taste buds on one's tongue are arranged into different groupings based on flavor. When a certain flavor is introduced, a specific area of the tongue is activated. With acidic foods, for instance, taste buds on the sides of the tongue produce a tingling sensation. When paired with other flavors, this acidity can add a pleasant crispness to foods. In other cases, such as when acidity is paired with bitter flavors, the results can be less than pleasant.
For people with particularly sensitive palates, acidic foods can produce far less pleasant reactions. In certain cases, a prolonged stinging or numbness may occur. Pain of the tongue -- known as Glossodynia -- can occur in any number of situations. In most cases, an antacid or even water can relieve this discomfort. If a person finds she has a painful reaction to acidic foods, she may want to do away with foods rich in tomatoes, pineapple, or other ingredients that are especially acidic.
In the presence of a canker sore, acidic foods should be avoided altogether. Canker sores are small, open sores on the inside of the mouth or tongue caused by a variety of culprits. They are harmless but can be painful. In certain cases, acidic foods may be the trigger for a canker sore. If the sore is already present, these foods can cause the sore to become worse or more irritated. When present on the tongue, canker sores can be treated with oral anesthetic gels.
When consumed at a high rate over a long period, acidic foods can cause a discoloration of the tongue. The normally pink tissue of the tongue can turn a bright red. In some cases, there may also be pain or irritation. Ceasing to eat acidic foods often causes the tongue's color to return to normal. If it doesn't, another cause may be the culprit. One possible solution may be a lack of iron or folic acid in the diet.