Human tongues may able to sense a sixth taste.
Researchers from New Zealand found that in addition to sweet, sour, salty, bitter and savory (umami), we may also recognize the taste of carbohydrates, according to Science Magazine.
In a recent study (full text), scientists found that the human brain reacts to the presence of carbohydrates in the mouth as if they had already been eaten. While participants' tongues were rinsed with one of three different fluids, they were simultaneously asked to squeeze a sensor held between their right index finger and thumb when shown a visual cue.
Two of the solutions were artificially sweetened while the third contained real carbohydrates in the form of sugar. When the real-sugar solution was used, the researchers observed a “30 percent increase in activity for the brain areas that control movement and vision,” says Science Magazine.
Scientists who conducted the study hypothesized that this sensory reaction was caused by our mouths anticipating a new energy source-- carbs.
The findings may indicate that human tastes are very perceptive when it comes to differentiating diet products from the real deal—and why they may be less satisfying even if they taste similar to their full sugar counterparts.
In the future, this research may guide the development of artificially flavored foods to reward both the human tongue and brain when it comes to cravings.