14 DAY TRIAL // You know that diet beverages have that artificial chemical disgusting taste that feels bad in your mouth. Of course, it comes from the chemicals (read sweeteners) they put in. Is it so?
A new research made at the University of Illinois reveals that, in fact, the bad taste of the light beverages is not given by the added chemicals but by a touch factor, called mouth-feel. Mouth-feel detects a food or beverage's body, fullness and thickness.
And the difference between a regular and a light variant of a beverage is due to the presence or absence of high-fructose corn syrup, which "softens" the drink.
The research team taught in a 4 weeks training program 12 subjects to employ in a 15-point scale assessing the features that give the mouth-feel of diet in regular soda. The subjects got so skilled that they could accurately detect extremely small differences in the mouth-feel of 14 samples. "We worked with solutions of sucrose and high-fructose corn syrup, asking panelists to detect when beverages began to differ from water in mouth-feel. And they were able to accurate identify varying degrees of viscosity on our 15-point scale." said co-author Soo-Yeun Lee, sensory scientist.
"The human mouth cavity appears to be a super-rheometer (the lab instrument that measures viscosity or thickness)," said co-researcher Shelly Schmidt.
In fact, the complex taste of the aliments is not given just by the taste sensors, but also mouth-feel, smell, vision and hearing. "If you bite into an apple and it doesn't crunch, it affects your perception of the way the apple tastes. And if a beverage doesn't feel right in your mouth, that affects your perception of the way the beverage tastes too." Lee said.
Many times, people experience a "halo effect": a non-taste food trait can increase the human perception of that food; if this decreases it, the trait is called "horns effect".
Color added to lemon-lime beverages made human subjects perceive the drink as more consistent, a clear halo effect. "But the color also led tasters to think the beverage had less carbonation, which it did not, meaning the color also conferred a horns effect," Lee said. "We think the lemon-lime flavor, which is exciting to the mouth, helps mask the mouth-feel difference, and that's why diet lemon-lime drinks were perceived as tasting more like their non-diet counterpoint than cola-flavored drinks. It's probably also the reason the new lime diet colas are so popular." said Lee.
Improving the mouth-feel of the light drinks would be a better choice for achieving their goal: fighting overweight and obesity. "Many people know they should cut calories, but they won't drink diet pop because they don't like the taste." said Schmidt.