Flavor vs Taste Experiment

Most of us use the terms “taste” and “flavor” interchangeably, but physiologists define these as two different things. Our overall impression of a food or beverage is called “flavor.” But every flavor impression is based on stimulus from three different senses: taste, aroma, and touch.

Our sense of taste comes from the tongue. The five well recognized tastes are sweet, salty, sour, bitter, and umami. (Recent research suggests that the tongue may also have taste receptors for fat, metallic, and carbonation). Beyond these basic tastes, the sensations we think of as being “flavor”—things like mint, banana, or cheese—result from stimulation of our olfactory nerves in our nasal passages. Of course this is what we normally think of as our sense of smell.

We often smell by breathing in through our nose. But we also smell the food in our mouth while we are eating by breathing out through our nose as we chew. As the air passes the back of your mouth on its way to the nose, it picks up aroma molecules. This type of smelling is called “retronasal” sensing of aroma.

The jellybean experiment helps to illustrate how important this retronasal route of smelling is to our perception of flavor.

When you hold your nose with one hand and pop one jellybean of unknown flavor into your mouth and start chewing, you will only be able to perceive the basic taste of the jellybean that comes from your tongue (mostly sweet). After you chew for five seconds or so, let go of your nose and notice what you taste.

Typically when you let go of your nose, the retronasal route quickly delivers aromas to your nose and the full flavor of the jellybean becomes apparent.

While many attributes of flavor depend on stimulus from your nose, your brain processes the aroma signals and makes you believe they are coming from your mouth. This experiment clearly demonstrates the role of retronasal smelling on our perception of flavor.