Sweet is generally considered to be the most pleasant taste. It is produced by a monosaccharide such as glucose or fructose, or a disaccharide such as sucrose. Because sugar is very important for animals to ingest energy for survival, it has a pleasant taste.

Common natural foods that contain sourness are fruits, such as lemons, grapes, oranges, and certain melons. Wine usually also contains a small amount of some kind of acid. If milk is not preserved properly, it will also become sour due to fermentation.

Salty taste is sensed through ion channels on taste cells and is mainly caused by sodium ions. Salty foods include light soy sauce, salted fish, and salted eggs. Saltiness can bring out the umami taste of meat, so when cooking seafood, you will add salt.

Bitterness is the most sensitive of taste, and many people understand it as an unpleasant and unacceptable sensation. Common bitter foods and beverages include coffee, original chocolate, bitter gourd, beer, olives, orange peel, many plants of the cruciferous family, young leaves of dandelion, and lettuce. The quinine found in the water of the cinchona tree cave is also famous for its bitter taste. On average, only 2.5 mg of quinine is needed to cause the bitter taste.

Umami is a kind of gustatory taste triggered by compounds such as glutamic acid, and is usually found in fermented foods. Under the combined action of sodium ions (the main component of table salt), glutamine is the freshest.