There is a persistent Life Saver rumor that harkens back decades. You’ve probably heard it yourself. It goes something like this: Wint-O-Green Life Savers give off bright sparks when bitten in a dark room. But is this an urban legend or does it have the glint of truth to it? If you answered “it’s true” you’re correct! But the mystery remains. How does it work?
For the answer, we went to the How Stuff Works web site. There we were in for a little surprise! “Actually, all hard sugar-based candies emit some degree of light when you bite them” according to their research. Usually, however, that light is very faint. “When you rip a piece of tape off the roll, it will produce a slight glow for the same reason,” the authors continue. And that reason is triboluminescence, the natural emission of light resulting from something being smashed or torn.
But there’s more to the story of Wint-O-Green Life Savers. When bitten, they shed a greater amount of visible light than other candies. And that extra spark is produced by the wintergreen flavoring. Oil of wintergreen is naturally fluorescent.
This means it absorbs the light of shorter wavelengths, in this case ultraviolet light, and then emits light of a longer wavelength in the visible spectrum. What results is a burst of blue sparks every time you crunch on a Wint-O-Green Life Saver!
To shed more light on the science behind this amazing Life Saver flavor, visit the Wint-O-Green page at How Stuff Works.