Taste and smell of food

When people think about the consumption of food and drink, the senses of taste and smell usually come to mind first. The chemical senses, smell and taste, play a key role in the sensory effects on appetite, food choice, and intake. They are intimately linked together from a perceptual perspective.

Smell, or olfaction, occurs when chemicals stimulate olfactory receptors located on a relatively small patch of tissue high in the nasal cavity. Smell plays the most important role in appreciating flavors in eating. Odor stimuli can reach the olfactory receptors in two ways: by entering the nostrils during inhalation (orthonasal route) or by traveling from the back of the oral cavity toward the roof of the nasal pharynx (retronasal route).

Taste, or gustation is experienced when food or drink, mixed with saliva, reaches tastebuds located on a large portion of the tongue ’ s dorsum and other parts of the oropharynx, such as the larynx, pharynx, and epiglottis. These are clustered in taste buds which are not visible to the naked eye. Most of them are buried in specialized structures called papillae on specific parts of the tongue.

While the sense of smell is involved in the anticipation of eating, as well as part of flavor perception during consumption, the sense of taste, by nature, is only in effect while food is ingested. Taste is primarily a nutrient sensing system. In contrast to the sheer infinite number of existing odor qualities, there are only a handful primary taste qualities: sweet, salt, umami, bitter, and sour.

Common “tastes” such as chocolate, coffee, strawberry, apple, peach, pizza, steak sauce, and chicken actually reflect smell mediated sensations: odors from chewing food are released and propelled upwards towards the olfactory receptors via the posterior nasal pharynx.
Taste and smell of food