January 19: What’s Popping on National Popcorn Day

Today’s the day! And if you’re wondering what today is, it’s popping day!

What’s popping?

There are six kinds of corn but only one of them can pop. Popcorn (the one that pops) is a maize plant with the scientific name Zea mays everta. Most of the popcorn in the world is grown in Nebraska and Indiana but farmers in Illinois and other Midwestern states also grow popcorn.

Popcorn plants can grow to over six feet tall and they also thrive in sandy soil which is not ideal for most other crops.

Americans eat more popcorn than anyone else in the world. Even our microwaves have special popcorn buttons.

Yoder Popcorn, Shipshewana, Indiana © Rex Vogel, all rights reserved

Popcorn is a favorite snack for many families and comes in a few different colors including red, blue, yellow, and white. It is easy to eat while playing cards or board games. Most people know popcorn is a favorite snack at sporting events and movies.

What makes popcorn a great snack?

It is a whole grain which means it contains the germ, endosperm, and pericarp (also known as the hull) and it is low in calories. Air-popped popcorn has 30 calories per cup. Oil-popped popcorn has 35 calories per cup. It also can be flavored with different herbs and spices to fit your taste or mixed with dried fruit, nuts, and cereal for a quick trail mix.

To keep popcorn as a healthy snack, be careful when adding salt and butter as they will add sodium, fat, and calories.

Yoder Popcorn, Shipshewana, Indiana © Rex Vogel, all rights reserved

What makes popcorn pop?

To look at what makes popcorn pop, we first have to understand what a popcorn kernel is made of. A popcorn kernel is composed of three main parts:

  • Germ
  • Endosperm
  • Hull/pericarp

The germ is found inside the shell and is considered the living part of the plant. The endosperm (also inside the shell) is a starchy area that provides nutrients for the germ. Finally, the hull is made of cellulose an indigestible sugar, and provides the hard outer shell. In popcorn, the hull is harder and thicker than in other types of corn.

Yoder Popcorn, Shipshewana, Indiana © Rex Vogel, all rights reserved

Why does popcorn pop?

A popcorn kernel must be able to withstand enough internal pressure for it to explode into our beloved snack. Popcorn’s thick hull is what allows this to happen. When you heat a kernel in the microwave, the microwaves transfer energy in the form of heat to the water inside the kernel.

The water absorbs the heat and it turns to steam and expands thus increasing the pressure inside the kernel. The pressure builds up inside of it to the tune of about 135 pounds per square inch.

This means that one little kernel explodes after resisting over 4 times the pressure inside car tires! When the pressure builds to an amount the hull can no longer contain, it explodes open resulting in a piece of popcorn.

Yoder Popcorn, Shipshewana, Indiana © Rex Vogel, all rights reserved

How high can popcorn pop?

Popping an afternoon snack of popcorn in the microwave generally isn’t a messy affair considering most popcorn cooking is contained in a bag. But if it wasn’t, you might have to watch out for flying kernels since popcorn can pop as high as 3 feet while it transforms from kernel to puff.

However, the tiny grains don’t just fly straight skyward as they expand; high-speed recordings of popcorn, as it cooks, show that the kernels actually flip like a high-flying gymnast thanks to starches that push off a cooking surface and propel the corn into the air. 

The way popcorn transforms from a hard nugget to a soft and springy morsel can seem like magic except scientists say it’s really just a trick caused by heat and pressure. As mentioned above each kernel has three parts: the germ (seed) found deep within the shell, the endosperm (a starch section used to nourish the germ if planted), and the pericarp (aka the hard exterior).

Moisture and starch are also packed into each tiny kernel; when heated, that microscopic amount of water creates pressurized steam. By the time a popcorn kernel reaches 350 degrees, the pressure is too much to contain and the pericarp explodes causing the starchy endosperm to expand outward. When the process is finished, the resulting popcorn has puffed up to 40 times its original size.

While the popcorn industry strives to get 98 percent popability from each bag of kernels, there’s likely still going to be duds at the bottom of the microwave bag. In those cases, it’s likely the pericarp was cracked or the kernel didn’t have enough internal moisture, both of which prevent any pressure buildup—which means that no amount of extra microwaving will give you a few more bites.

Yoder Popcorn, Shipshewana, Indiana © Rex Vogel, all rights reserved

Popcorn pops into two distinct shapes

When popcorn is all lumped together in a bowl, it just looks like… popcorn. But an up-close inspection shows that kernels pop into one of two shapes transforming into butterflies and snowflakes (winged, multifaceted shapes) or mushrooms (rounded puffs).

Butterflies occur when the popped kernel turns inside out while mushrooms are created when the kernel’s endosperm expands instead of flipping. Generally, mushrooms are sturdier and can withstand the additional cooking process to become caramel or kettle corn.

Whether your bowl of popcorn gets more mushrooms or butterflies mostly depends on factors uncontrollable from your kitchen like the popcorn plant’s genetics or how much water the plant received while it was growing in the field.

Yoder Popcorn, Shipshewana, Indiana © Rex Vogel, all rights reserved

Fun facts about popcorn

  • According to the USDA, Nebraska and Indiana grow most of the popcorn
  • Nebraska produces an estimated 250 million pounds of popcorn per year—more than any other state
  • Americans eat around 17 billion quarts of popcorn every year; this amount would fill the Empire State Building 18 times
  • Popcorn can pop up to three feet in the air
  • If you made a trail of popcorn from New York City to Los Angeles, you would need more than 352,028,160 popped kernels
  • General Mills patented the first modern microwave popcorn bag in 1981
Yoder Popcorn, Shipshewana, Indiana © Rex Vogel, all rights reserved

Popcorn is not just for eating

Check out the following ideas for other ways to use popcorn:

  • Stringing popcorn: These can be hung outside for birds to eat or hung on your Christmas tree
  • Popcorn air hockey: Use a straw to blow the kernels back and forth or your hands as paddles to volley the kernel back and forth 20 times without letting it fall
  • Popcorn relay race: In teams, use spoons to transport popcorn back and forth
  • Popcorn basketball: Flick a piece of popcorn into the basket (muffin tins, small cups or your own mouth)

By the way, I have another post on National Popcorn Day: January 19: However You like Popcorn Enjoy It TODAY on National Popcorn Day

Related popcorn days

  • National Caramel Popcorn Day (April 6)

Worth Pondering…

Have you ever pondered the miracle of popcorn? It starts out as a tiny, little, compact kernel with magic trapped inside that when agitated, bursts to create something marvelously desirable. It’s sort of like those tiny, little thoughts trapped inside an author’s head that―in an excited explosion of words―suddenly become a captivating fairy tale!

―Richelle E. Goodrich