Triboluminescence: Solving the Mint Candy Mystery

Did you know that munching on certain mint Life Savers can cause a blue spark to occur? The next time you’re in the mood for a tasty science experiment step into a dark room with a mirror and pop a few wintergreen Life Savers in your mouth. The blue flashes that sparkle as you crunch on them is actually a fascinating light reaction known as Triboluminescence.

Triboluminescence is the phenomenon in which light is produced from friction. In a much smaller sense, our candy crunching mimics the way lightning is produced in the sky. Nitrogen gas becomes excited in the air and creates that blue-white light. When we chew on wintergreen-flavored Life Savers, we create spots of positive and negative charges in the sugar crystals. When these build up, electrons (negative charges) jump across tiny fractures in the crystal. When this happens they collide with nitrogen gas molecules in the air. The nitrogen molecules become positively charged ions and combine with the wintergreen oil in the candy the reaction produces a blue luminescence (glow).

The exact cause of this reaction is still unknown; however, researchers believe this light reaction is created by an electrical charge. Similar reactions occur when you pull band-aid wrappers apart and separate the charged atoms in the adhesive. The release of energy creates a cracking sparkle very similar to Triboluminescence. Unfortunately for science, once the candy gets soggy the effect stops and so each spark lasts only a few milliseconds, but for us, it’s a great excuse to keep “experimenting”!