The glow of food dye can be used to monitor food quality

Allura Red, a synthetic food and pharmaceutical color widely used within the U.S., boasts special properties that may make it and other food dyes appropriate as sensors or edible probes to monitor foods and pharmaceuticals. A team of researchers recently made this discovery during an extension of their work identifying and characterizing molecules in foods or food ingredients that might provide signals of food quality, stability or safety.

(via WSJ)