Explanation: Jawbreaker candies have a not-so-sweet reputation for inflicting bodily harm. Around the country, police reports detail incidents of the gobstoppers exploding in — and on — kids' faces, leaving severe burns. But why would these confections turn so sour?
MythBusters Jamie Hyneman and Adam Savage noticed that many of the injured kids first heated their jawbreakers in the microwave, and when they bit or licked them afterward, the candy blasted open.
Slicing a jawbreaker opens reveals why the microwave might aggravate that cement-like sugar. The candies are formed from multiple layers of sugary syrup surrounding a solid candy core encased in a hard outer shell. That jawbreaker architecture can cause a temperature differential, meaning that the internal layers can heat up faster than the outer ones.
For that reason, when the MythBusters tossed some jawbreakers into a microwave, then crunched the hot candy in a pair of steel jaws, the molten insides spewed out. As a painful confirmation to the myth, the 225-degree gobstopper goop scorched Jamie's unprotected arm.