Many grains are called corn
Humans eating popcorn is as old as civilization. In fact, it is believed to be the first way that humans consumed corn. While the term 'corn' has been in use for centuries, at first is was merely a term to describe the common grain of an area. Corn could be barley or oats, depending on whether you were in England, Scotland or Ireland, while rice was the only corn said to grow in the East Indies (Indonesia and south east Asia.) So, corn had many meanings when explorers encountered it as they reached the New World. They called this grain corn too. However, they soon adopted the word maize, which is an adaptation by Spanish explorers from the Haitian word mahiz and it was also called Indian Corn, however that was soon shortened to just 'corn'.
Early popcorn history
The Aztecs were probably the first to domesticate the tiny little nubs they called teosinte about 6000 B.C.E. It looked nothing like the roasting ears we are familiar with today and they stuck these little thumb-sized ears on sticks and held them in the fire to pop the tiny kernels. The first corn was all popcorn. The softer dent and flint corn that made tortillias and a type porridge came much, much later. They thought so much of popped corn that they designated several special gods just for overseeing its health and productivity during the various stages of growth and old pottery and murals depict high-ranking rulers wearing head dresses decorated with the popped ears. It was a main source of nutrition for these early peoples in central Mexico and while corn by itself isn't actually all that nutritious, when combining it with beans, it has all the essential amino acids to make it a perfect protein. They called corn, beans and squash the Three Sisters and these people could exist for long periods of time on just those foods. About 2500 years ago, the grain we call corn made its way into what is now the Southwest U.S. and sometime later, further east. The eastward movement was slow, however the Iroquois of North America's Northeast popped corn about 600 years ago, so there seems to be validation that trade went on between tribes and communities separated by long distances.
Popcorn gains new fans
Popcorn didn't really catch on with North American settlers until the 19th Century. People ate popcorn like we do breakfast cereal with milk and sugar. In fact, the name popcorn wasn't even entered into the dictionary until 1848. Until then, it was called 'pearls' or 'nonpariels'. The name change didn't really do much for popcorn's popularity. In fact, it was the creation of an iconic snack in the 1890's that changed how America ate popcorn. The name, 'Cracker Jack' (which was actually a Victorian Era slang term describing something of excellent quality), was registered in 1896 and the rest is history. Also, in 1908, Cracker Jacks got some free publicity when the song 'Take Me Out to the Ball Game' (yes, that one...we all know it) was released. Even though sugared or molasses covered popcorn had been around for several decades, this combination of peanuts, popcorn and syrup really put our first junk food on the map.
Popcorn and the movies
Movie theater popcorn happened some time later. It seems that theater owners thought that customers eating popcorn would detract from the show and resisted offering it for sale. However enterprising street vendors would walk up and down the aisles selling it anyway. Then in 1938, the first popcorn poppers were brought into the theaters and business boomed. Since popcorn is bought by weight and sold by volume, it is one of the most profitable things a movie theater (or sports arena) can sell. It was still popped the old fashioned way with hot oil, and it wasn't until 1981 when the first microwave popcorn bag was introduced that our love affair with this ancient grain was rekindled. Americans now consume 17 billion quarts of popcorn each year thanks to the microwave. This amount of popcorn would fill the Empire State Building 18 times over.
Why does popcorn pop?
But just what makes popcorn pop? It isn't all that complicated. The hard shells hold moisture better than modern dent or flint corn and the embryo (what germinates into a corn plant) is surrounded by liquid starch, which would feed the little plant if it wasn't popped. The hard kernel acts like a pressure cooker and the starch builds up pressure as the temperature rises. At about 450 degrees, the starch turns to steam and expands, which explodes the kernel. For perfect popcorn, the moisture content needs to be between 14% to 15%. Any more and the kernels will not fluff up properly and any less the kernels might not pop at all. Popcorn farmers store their popcorn after harvest until the moisture content, like Goldilocks' porridge is just right. Freshly harvested popcorn has a much higher moisture content and needs this storage period to be at its best.
Growing popcorn is no different than any other corn. It is an annual plant that does best between USDA Zones 4-9 because it needs warm summer temperatures. You also need at least eight hours of sun each day and fertile loam. Popcorn is a nitrogen hog like other grasses, so an all purpose NPK fertilizer with the N having the highest number is recommended. Plant seed outdoors when all danger of frost has passed and plant your popcorn in blocks of at least four rows instead of one long row. Popcorn, like other corn has wind-borne pollen and you will have fuller ears when the plants are planted in groups. The Native People planted their corn in a spiral, which also works well too. Popcorn has smaller ears and shorter plants than our regular sweet corn and there are varieties with different maturity dates so that northern gardeners can grow it just like southern gardeners. Don't worry about GMO (genetically modified) popcorn. There are no GMO popcorn varieties available to plant at this time. Once the corn ears have formed, leave them on the plant until they are dry and crispy. If wet weather threatens after the ears have dried, remove them and let them continue to dry indoors. Test a few kernels at a time in hot oil and when they all pop up white and fluffy, store your popcorn in a sealed container.
Popcorn is still a popular snack
Popcorn is one of our oldest foods and even though it is now designated as a snack food, that doesn't make it any less attractive. We love our popcorn. The smell of it wafts through movie theaters, sports stadiums and living rooms around the world. We season it with so many things because it is so versatile. What other snack could be salty, buttery, spicy, sweet, garlicky, lemony, peppery, cheezy, chocolately or fruity? Gourmet popcorn companies ship exotic flavors wherever popcorn lovers live and less expensive alternatives line the aisles of big box stores in decorative tins every holiday season. Along with Cracker Jacks, there's a huge list of choices even in the grocery stores. Popped popcorn snacks line the shelves along with potato chips and tortilla chips. Jiffy Pop comes in its own aluminum pan so you can take it to camp outs and bonfires, however I remember when that item was a novel treat cooked on top of the stove, so that's probably giving you a hint of my age. If you don't want to rely on companies to pop and season your corn, you can buy the exotic seasonings to sprinkle on yourself. Popcorn is a big business and it is amazing that it has stood the test of time for thousands of years. There's very few foods that can claim that.