flavor, attribute of a substance that is produced by the senses of smell, taste, and touch and is perceived within the mouth.
Tasting occurs chiefly on the tongue through the taste buds. The taste buds are stimulated by five fundamental taste sensations—sweet, salty, sour, bitter, and umami. Substances can be tasted only when they are in water solutions, and if a substance is not in solution when taken into the mouth, it must be dissolved in saliva before it can be detected by the taste buds. The taste buds most sensitive to salty sensations are dispersed along the sides and front of the tongue, while those most sensitive to sweetness are concentrated on the tip of the tongue. Taste buds at the rear of the tongue are the most responsive to bitterness. Sourness is best detected by taste buds on the tongue’s sides.
The sense of smell involves the olfactory nerve endings in the upper part of the interior of the nose. Aromas can reach these nerves either directly through the nostrils, as in breathing, or indirectly up the back passageway from the mouth. Because of their remote location, the olfactory nerve endings are best stimulated by inhaling through the nose or swallowing if food is in the mouth. Odors are detected only when the material is in gaseous form—i.e., a dispersion of molecules in air. Disorders of smell greatly affect a person’s ability to detect flavors.
Touch sensations that contribute to taste originate in the nose, on the lips, and throughout the entire mouth and throat. The touch sensations relating solely to flavor are based on the chemical properties of the substance. Reactions induced by chemical properties include the coolness of peppermint, the “bite” of mustard and pepper, and the warmth of cloves.
When someone consumes food, the simultaneous stimulation of the senses of taste, smell, and touch creates an immediate impression—which can be understood as flavor—that causes that person to accept the food and continue eating it or to reject it. Many foods such as bananas, berries, and other fruits, nuts, milk, and a few vegetables have flavors that make them highly acceptable in their natural, uncooked state. Other foods derive their flavor through cooking, seasoning, or some combination of these and other processes. Preference for or avoidance of a particular flavor is a learned behavior.