Q: How does popcorn pop?A: Popcorn kernels...

Q: How does popcorn pop?

A: Popcorn kernels contain starch grains embedded in a very strong protein matrix, or framework. When the kernel is heated quickly to about 150 degrees Fahrenheit, water in the starch vaporizes, softening it. The starch rapidly expands in volume, breaking open the protein matrix with tremendous pressure, producing the popping sound. Slow heating causes the water to escape, and the corn does not pop.

The idea of popping corn is at least 5,000 years old, according to “Science and Technology Desk Reference.” In 1952, the late Orville Redenbacher and Charles Bowman bred a popcorn whose kernels seldom failed to pop, but popcorn makers refused to buy the higher-priced product, fearing consumers would rebel at increased prices. Redenbacher eventually marketed it himself. Americans now eat an average of two pounds of popcorn a year.