Engineering Pop Rocks

How One Chemist Created a Classic Candy:

If you’re a child of the 70s, or any decade after for that matter, you’ve probably had Pop Rocks. There’s something unique and exciting about a candy you can hear fizzle in your mouth and stomach. But where did Pop Rocks come from?

History of Pop Rocks

Like most modern candy, it’s all in the science. In 1956, food chemist William A. Mitchell, the same scientist behind Jell-O, Tang, and Cool Whip, was designing an instant soda made from carbonated Kool-Aid.

Mitchell added carbon dioxide into sugar, but instead of a rapid soda, he had a candy that popped when exposed to high temperatures or liquids.

How Are Pop Rocks Made?

Today’s Pop Rocks have sugar, lactose (milk sugar), corn syrup, and artificial flavors and colorings, but the secret popping sauce is carbon dioxide.

Factory machines mix sugar, corn syrup, water, and other flavorings. Once heated, the sugar dissolves and the water evaporates, leaving a syrup-like mixture. Workers gasify the syrup and add 600 pounds per square inch of CO2. This cooled, gasified creation becomes brittle and shattered, trapping some of the CO2 inside.

When you toss back a handful of Pop Rocks, your saliva dissolves the candy’s outer coating and…POP! The trapped CO2 bubbles escape.

Can Pop Rocks and Coca-Cola Kill You?

No! The theory is that the Coke and Pop Rocks will trap too much CO2 in your stomach, causing it to expand until it explodes. However, there isn’t enough CO2 in either to cause an explosion. Just excess burping.

Can I Make Pop Rocks at Home?

Not without difficulty. The ingredients are simple enough, but the process requires high pressure and just the right amount of each ingredient. It takes a special team to get it right. One engineer managed to make his own Pop Rocks using a high-pressure chamber: