On this Wikipedia the language links are taste of home scalloped potatoes and ham the top of the page across from the article title. This article is about the sense. The tongue is covered with thousands of small bumps called papillae, which are visible to the naked eye.

Within each papilla are hundreds of taste buds. As the gustatory system senses both harmful and beneficial things, all basic taste modalities are classified as either aversive or appetitive, depending upon the effect the things they sense have on the body. Sweetness helps to identify energy-rich foods, while bitterness serves as a warning sign of poisons. Among humans, taste perception begins to fade at an older age because of loss of tongue papillae and a general decrease in saliva production. This section needs additional citations for verification. Please help improve this article by adding citations to reliable sources. The gustatory system allows animals to distinguish between safe and harmful food, and to gauge foods’ nutritional value.

Digestive enzymes in saliva begin to dissolve food into base chemicals that are washed over the papillae and detected as tastes by the taste buds. As of the early 20th century, Western physiologists and psychologists believed there were four basic tastes: sweetness, sourness, saltiness, and bitterness. The concept of a “savory” taste was not present in Western science at that time, but was postulated in Japanese research. However, acids are also detected and perceived as sour.

Sour and salt tastes can be pleasant in small quantities, but in larger quantities become more and more unpleasant to taste. For sour taste this is presumably because the sour taste can signal under-ripe fruit, rotten meat, and other spoiled foods, which can be dangerous to the body because of bacteria which grow in such media. Additionally, sour taste signals acids, which can cause serious tissue damage. Sweet taste signals the presence of carbohydrates in solution.