Did you know you can make little bolts of lightning in your mouth? Just chew on some wintergreen Lifesavers candy. It’s been observed since the 1980s that this particular flavor of Lifesavers has the curious habit of emitting sparks inside your mouth when you chew them. The sparks are electricity. This is caused by a phenomenon called triboluminescence, a word coined in 1895. It occurs when certain substances are crushed, broken, or rubbed. Most of these, like some quartz crystals and mica, aren’t good for eating, unfortunately but Wintergreen Lifesavers (Wint-O-Green), if you like that sort of thing, are both a tasty treat and a science experiment in your mouth.
So why do wintergreen Lifesavers give off sparks of electricity when you chew them? It has to do with sugar crystals in the candy. When sugar crystals are fractured, different areas of positive and negative charge form on opposite sides of cracks in the crystals. These different charge cause electrons to jump back and forth between the gaps in the crystals to stabilize the charge. When all those little electrons are jumping around, they come into contact with nitrogen in the air. And, there is a lot of nitrogen in the air. You thought oxygen was a big deal? Air is 78% nitrogen. When nitrogen comes into contact with electrons, it emits little bolts of lightning. It’s true! These little blue-white sparks of electricity are the same wavelength as lightning. You can actually create this effect by rubbing sugar crystals together. It also happens sometimes when adhesive tape is pulled away from a surface.
However, this effect us usually pretty small and weak with sugar crystals so you won’t normally see the little sparks, if they are produced. wintergreen Lifesavers possess a double-helping of luminescence. Dr. Linda Sweeting, who has studied triboluminescence extensively, theorized in 1988 that the triboluminescence of the sugar crystals in the candy gets a boost from another ingredient, the oils of the wintergreen flavoring.
Wintergreen is not triboluminescent; it’s fluorescent. This means that it absorbs ultraviolet light and re-emits it as light that is visible to us. You’ll be familiar with this effect from various black-light posters. When you chew on wintergreen Lifesavers and the sugar-crystals start emitting light, some of that light is ultraviolet. This ultraviolet light excites molecules in the wintergreen oil and causes it to fluoresce. It’s as if the wintergreen oil acts like an amplifier, taking the weak little burst of ultraviolet, getting all excited about it, and bursting out little sparks that we can see, as long as we chew with our mouths open. Which is rude unless you ar eating Wintergreen Lifesavers, when it’s for science. Of course, you’ll see the light much better in a darked or dimly lighted room.
The best method of creating the sparks from Wint-O-Green Lifesavers is by crushing them with a hammer in a dark room, as did the YouTube Channel Smarter Every Day, while filming with a high-speed camera.
