Only popcorn kernels can pop, and the secret is water. Each kernel contains a small amount of water stored in a circle of soft starch inside the hard outer casing. When heated to around 230°C, the moisture turns to steam, creating pressure within. As the pressure builds, the casing eventually gives way, and the kernel explodes and pops, allowing the water to escape as steam and turning the kernel inside out.
Here’s some interesting information about the history of popcorn:
No one knows exactly where popcorn came from or when it was first popped, but archaeologists have been “hot” on the popcorn trail, and they have found popcorn in some most unusual places. One such place was the tombs on the east coast of Peru where they found grains of popcorn that were a 1,000 years old. These grains were so well preserved that they still popped! Ears of popcorn were also found in the Bat Cave of West Central New Mexico that were nearly 5,600 years old. One of the oldest finds of popcorn was made in Mexico City where 80,000-year-old fossilized corn pollen was found buried 200 feet below the city!
Archaeologists believe that popcorn originated in Mexico, but they know that it was grown in China, Sumatra, and India years before Columbus visited America! By the time Columbus arrived in 1492, popcorn was widespread throughout North and South America and was enjoyed by most Native American tribes. The natives of the West Indies even tried to sell popcorn to Columbus and his crew, but it wasn’t until the first Thanksgiving Feast at Plymouth, Massachusetts that the English colonists were introduced to popcorn. As a gift for the celebration, Quadequina, brother of the Wampanoag chief Massasoit brought a deerskin bag of popped corn. He certainly understood how to make friends fast!