What’s That Taste?

Taste buds contain receptors to detect molecules in food and are concentrated on the tip, sides and back of the tongue.


The sensation of sweetness is usually caused by sugars such as fructose, lactose, aspartame and saccharin. Other substances (alcohols, amino acids) can also activate cells that respond to sweetness.


Sour flavors are generated mostly by acidic solutions such as lemon juice or organic acids. The sensation is linked to hydrogen ions in solution.


Food containing table salt is mainly what we taste as salty. Mineral salts (potassium or magnesium) can also cause a sensation of saltiness but can also be bitter.


A bitterness sensation is brought about by many different substances, such as quinine or caffeine. About 35 different proteins in sensory cells respond to bitter substances.


The “umami” taste is somewhat similar to the taste of meat broth. Glutamic is largely responsible for these flavors. Ripe tomatoes, meat and cheese all contain glutamic acid.


Complex carbohydrate molecules are thought to be too large to interact with our taste receptors. Juyun Lim and her research team at Oregon State have found that carbs in rice, potatoes and other starchy foods generate a taste response. (See A Sense for Starch)

Adapted from the U.S. National Library of Medicine