How Taste Works
Taste signals begin when molecules from food or beverages interact with receptors in highly specialized cells in the taste buds of the tongue. The signals are then propagated along sensory nerves to the brain, where they create a perception about the nature of the substance in the oral cavity, and whether that substance should be ingested or rejected. The final determination is the result of a cognitive analysis of two sensory characteristics: taste quality and palatability.
Taste quality is the recognition of a taste stimulus as being similar or different from a familiar taste, especially the basic tastes: sweet, salty, bitter, and sour. We perform a taste quality analysis whenever we ask, “What does this taste like?” Comparisons to more complex tastes can also be considered a function of taste quality. For example, we might regard something as having a “chocolatey” taste. In more operational terms, taste quality is the result of discrimination from or generalization to a standard taste cue.
Palatability is the property of taste that determines whether we like or dislike a substance in the oral cavity—“how good, or bad, does something taste?” Palatability is a sensory characteristic closely associated with the nutritive value of food. For example, highly palatable foods and beverages are often calorie-dense, and as a result, they tend to be over-consumed. However, some non-caloric sweeteners used in diet drinks are considered highly palatable as well. Palatability can be operationally defined as the probability that a food or beverage will be consumed.