Pop Rocks

Pop Rocks are a kind of candy with carbonation added to make a "popping" feeling in the mouth of the person eating them.

Red-colored Pop Rocks

How do they pop?

The candy pops and fizzes because it contains bubbles of carbon dioxide under high pressure. When you melt the candy shell, the carbon dioxide escapes with a pop. When Pop Rocks® are made, the hot candy syrup is mixed with carbon dioxide gas under high pressure (600 pounds per square inch).

Other websites

• Images of US patent 4289794 for Pop Rocks Archived 2007-11-06 at the Wayback Machine from the U.S. Patent and Trademark Office
• Pop Rocks: The Inside Story of America's Revolutionary Candy, book detailing the story of Pop Rocks development to Pop Rocks today
• How do Pop Rocks candy work?, an article from HowStuffWorks that explains how pop rocks candy is manufactured and also has links to the original patent