Scientists at the University of Illinois at Urbana-Champaign and funded by the National Institutes of Health have developed an “electronic tongue” that accurately identifies sweetness, one of the 5 primary tastes. Reported at the American Chemical Society’s 238th National Meeting in Washington, DC, in August 2009, the “tongue” is a small, inexpensive, sensor about the size of a business card that can identify with 100% accuracy the full sweep of natural and artificial sweet substances, including 14 common sweeteners, using easy-to-read color markers. Not only does this device show promise in quality control testing that food proc-essors can use to ensure that their products taste great, with a consistent, predictable flavor, but in the future, doctors and scientists could use modified versions of the sensor for chemical-sensing applications ranging from monitoring blood glucose levels in people with diabetes to identifying toxic substances in the environment, according to researchers. “We take things that smell or taste and convert their chemical properties into a visual image,” says study leader Kenneth Suslick, PhD. “This is the first practical ‘electronic tongue’ sensor that you can simply dip into a sample and identify the source of sweetness based on its color.” The sensor has identified 14 different natural and artificial sweeteners, including sucrose (table sugar), xylitol (used in sugarless chewing gum), sorbitol, aspartame, and saccharin with 100% accuracy in 80 different trials. The sensor produces results in about 2 minutes. More work is required to develop the technology into a complete electronic tongue that can detect the 5 main human tastes: sweet, sour, salty, bitter, and umami (meaty or savory).
(Source: ScienceDaily, August 18, 2009)
