Smaakzin

Smaakzin is the Dutch term for the gustatory sense, the sense of taste. It encompasses the detection of basic tastants by taste receptor cells and the processing of gustatory information by the nervous system. The sense contributes to nutrition, safety, and flavor perception, and its sensitivity varies with genetics, age, health, and culture.

Taste receptor cells are grouped in taste buds, located mainly on the tongue within structures called papillae—fungiform on the tip and sides, circumvallate and foliate at the back and sides. Each taste bud contains receptor cells responsive to five basic tastes: sweet, sour, salty, bitter, and umami (savory). Salt and sour mainly involve ion channels, while sweet, umami, and bitter use G protein-coupled receptors to detect specific molecules.

Signals from taste buds are transmitted primarily by cranial nerves VII (facial) via the chorda tympani, IX (glossopharyngeal), and X (vagus) to the brainstem's solitary nucleus, then to the thalamus and finally to the gustatory cortex in the insula and frontal operculum.

Flavor perception results from integration with retronasal olfaction (smell from the mouth) and textural cues, so taste is only one component of flavor.

Genetic factors influence sensitivity to certain tastes (for example, TAS2R38 bitterness). Taste preferences can be shaped by early exposure, culture, and learning; preference for sweetness is common in infants but changes with age. Taste sensitivity often declines with aging.

Impairments such as ageusia (loss of taste), hypogeusia, or dysgeusia can occur due to infections, medications, zinc deficiency, cancer therapies, neurological disorders, or head trauma, affecting appetite and nutrition. Conditions may be temporary or persistent.