At this week’s American Chemical Society’s 238th National Meeting, researchers from the University of Illinois at Urbana-Champaign presented a study about a sensor that can accurately detect the presence of any of the common sweeteners used in food products. The business card size sensor has color spots that activate when particular chemicals are detected, and the color pattern as a whole identifies the actual sweetener in drinks and even solid foods.
“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.”
Researchers have tried for years to develop “electronic tongues” or “electronic noses” that rival or even surpass the sensitivity of the human tongue and nose. But these devices can generally have difficulty distinguishing one chemical flavor from another, particularly in a complex mixture. Those drawbacks limit the practical applications of prior technology. Suslick’s “lab-on-a-chip” 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.