Eyes might be the window to the soul, but the nose is a window to mood. Photo: Flickr via Creative Commons/pedrosimoes7
Scientists have reported that the odor sensors in the nose are also present in human taste cells on the tongue. New research revealed the possible interactions between the senses of smell and taste, which are both responsible for the food flavor.

“Our research may help explain how odor molecules modulate taste perception,” Dr. Mehmet Hakan Ozdener, a cell biologist at Monell and the study’s senior author, said in a statement. “This may lead to the development of odor-based taste modifiers that can help combat the excess salt, sugar, and fat intake associated with diet-related diseases such as obesity and diabetes.”

People misunderstand that flavor is not equal to taste. The unique flavor of foods and beverages comes more from smell than it does from the actual taste. The sense of taste in the tongue identifies whether or not something is sweet, salty, sour, bitter or savory (umami), as well as determine the nutritional value or potential toxicity of the molecules that come in contact with the mouth.

Sense of smell, however, gives detailed information about the quality of food flavor. It combines the input from the taste, smell and other senses to create the multi-sensory process of flavor identification.

For example, bananas, mangoes and cherries are all sweet, but their smell provides depth to their taste that makes them unique from one another.

Taste and smell were considered a separate sensory system that do not interact until their individual information reaches the brain. Ozdener was urged to challenge this idea when his 12-year-old son asked him if snakes extended their tongues so they can smell.

In a paper published in the Journal of Chemical Sense, Ozdener and his colleagues from the Monell Centerreported that human taste cells contain many key molecules recognized to be found in the olfactory receptors of the nose.

The findings demonstrate a model system of olfactory receptor, or odor receptor, interacting with taste receptors of the tongue. This supports the possibility that a single taste cell may contain both taste and olfactory receptors.

“The presence of olfactory receptors and taste receptors in the same cell will provide us with exciting opportunities to study interactions between odor and taste stimuli on the tongue,” Ozdener said.

The result of the study pushes scientific understanding of how the olfactory system detects odors. As of the moment, scientists are unaware of the molecules that activate 400 different types of olfactory receptors.

Scientists will continue study whether or not odor receptors are specially located on a specific taste cell type, for example, sweet- or salt-detecting cells. Other works will explore how odor molecules adapt to taste cell responses and, eventually, taste perception.

Source: Sense Interaction: Smell Using Your Tongue

Random sensory quotes

People who read poetry, for example, like the feel, the heft and the smell of a book.

— Simon Armitage