We know that our perception of flavor involves a complex interaction between odors detected in the nose and tastes sensed by our tongue. A fascinating new study has turned the science of flavor perception upside down, discovering the same olfactory receptors that detect odors in our nose can be found in taste cells on the tongue.
Anyone who has ever suffered through sinus problems would be acutely aware of the influence smell has over taste. Even a minor cold blocking up the nose can result in food suddenly becoming unexpectedly bland. While there is debate over exactly how much of what we perceive as taste comes from our sense of smell, it is inarguable that smell is a profoundly dominant sense in determining our perception of flavor.
Traditional thought suggests that our overall sensation of flavor is generated deep inside the brain, when taste and smell inputs are ultimately combined into one sensation. An incredible new study is shaking up that assumption with the revelation that our tongues actually carry odor receptors, suggesting the smell of certain foods can directly modulate taste information that is captured by the tongue.
Using mouse models and human taste cell cultures, the researchers first discovered that olfactory receptors can be found in taste cells. Closer study, using a technique called calcium imaging, further revealed that these olfactory receptors are indeed functional, responding to odors in a manner similar to that seen in the same receptors located in the nose.
The new research perhaps raises more questions than it answers, particularly around how these tongue-located olfactory receptors communicate with the brain. However, the implications of the discovery suggest fascinating future research directions for understanding how the smell of food can interact with taste signals on the tongue.
"Our research may help explain how odor molecules modulate taste perception," explains senior author on the new study, Mehmet Hakan Ozdener. "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."
One potential outcome of this discovery is the possibility of minor sweet odor characteristics being added to food so as to trick the tongue into sensing something as being sweeter than it actually is. It is still early days for the research but discovering that single cells on the tongue can contain both odor and taste receptors will direct scientists toward a whole new understanding into how humans ultimately perceive taste.
The new research was published in the journal Chemical Senses.
Source: Monell Chemical Senses Center
