You can't help but wonder how people originally figured out how to eat some of today's favorite foods. The
manioc plant is poisonous unless it is carefully processed through multiple steps. Yogurt is essentially old milk that has been stored for a long time and has been contaminated with bacteria.
And who discovered that you can get delicious popcorn after heat treating corn? Such nutritional mysteries are quite difficult to solve.
Archaeology relies on solid remains to figure out what happened in the past, especially when it comes to people who didn't use any writing.
Unfortunately, most things that people traditionally used, made of wood, animal materials, or cloth, decompose pretty quickly and archaeologists never find them. Archaeologists have a lot of evidence of hard objects like pottery and stone tools, but softer things - like food scraps - are much harder to find.
Sometimes you are lucky if soft items are found in very dry places where they are preserved. Also, if the items are burned, they can be preserved for a very long time.
The ancestors of corn
Fortunately, corn - also called maize - has hard parts, like the shell of the kernel. These are the bits at the bottom of the popcorn bowl that get stuck in your teeth. And because corn has to be heated to make it edible, it sometimes burned, and archaeologists are finding evidence of that. Most interestingly, some plants, including corn, contain tiny, rock-like fragments called phytoliths that can persist for thousands of years.
Photo: theconversation.com
Scientists are confident that they know how old corn is. What is known is that corn was probably first cultivated by Native Americans in what is now Mexico. Early farmers domesticated corn from a grass called teosinte.
Before the advent of agriculture, people collected wild teosinte and ate its seeds, which contain a lot of starch, a carbohydrate found in bread or pasta. They collected the teosinte with the largest seeds and eventually began weeding and planting it. Over time, the wild plant evolved into something similar to what humans today call corn. You can tell the difference between corn and teosinte by the larger kernels.
Evidence that corn was grown in the dry caves of Mexico was found as far back as 9,000 years ago. From there, corn spread throughout North and South America.
Specialty corn varieties, food preservation
Figuring out when people started making popcorn is more complicated. There are several types of corn, most of which burst when heated, but one variety, actually called "popcorn," makes the best product. Scientists discovered phytoliths from Peru as well as burnt kernels of this type of "popcorny" corn as far back as 6,700 years ago.
Photo: theconversation.com
One can imagine that the first time this way of cooking corn kernels was discovered by accident. Probably some corn fell into the fire, and whoever was nearby realized that this was a new convenient way of cooking. Corn kept for a long time and was easy to prepare.
Ancient popcorn probably wasn't much like the popcorn you can eat in a movie theater today. It probably didn't have salt and definitely didn't have butter, since there were no cows to milk in America yet. It probably wasn't served hot and was quite "chewy" compared to what people are used to today.
It's impossible to say exactly why or how popcorn was invented, but presumably it was a clever way to preserve the edible starch in corn by getting rid of the small amount of water inside each kernel that makes it more susceptible to spoilage.
It is the heated water in the kernel, escaping as steam, that makes the popcorn burst and pop open. Popcorn can then be stored for a very long time. The preparation of what is now considered a tasty snack may have started as a useful way of preserving and storing food.