Washington D.C.— In a new approach to an effective “electronic tongue” that mimics human taste, scientists in Illinois are reporting development of a small, inexpensive, lab-on-a-chip sensor that quickly and accurately identifies sweetness. It can identify with 100 percent accuracy the full sweep of natural and artificial sweet substances, including 14 common sweeteners, using easy-to-read color markers.
This sensory “sweet-tooth” shows promise as a simple quality control test that food processors can use to ensure that soda pop, beer, and other beverages taste great with a consistent, predictable flavor. Their study was described at the American Chemical Society’s 238th National Meeting.
The sensor, about the size of a business card, can also identify sweeteners used in solid foods such as cakes, cookies and chewing gum. “We take things that smell or taste and convert their chemical properties into a visual image,” says study leader Kenneth Suslick, Ph.D., of the University of Illinois at Urbana-Champaign. “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.”
Suslick’s team has spent a decade developing the colorimetric-sensor-array chip which consists of a tough, glass-like container with 16 to 36 tiny printed dye spots, each the diameter of a pencil lead. The chemicals in each spot react with sweet substances in a way that produces a color change. The colors vary with the type of sweetener present, and their intensity varies with the amount of sweetener.
Christopher Musto, a doctoral student in Suslick’s lab, says it will take more work to develop the technology into a complete electronic tongue. “To be considered a true electronic tongue, the device must detect not just sweet, but sour, salty, bitter and umami — the five main human tastes,” he says.
The National Institutes of Health funded the research. An Illinois-based company, iSense, is commercializing the technology. Sung H. Lim also contributed to the research study.
The complete story can be read at ACS.org.