The Science and History of Popcorn – the Snack that Saved the Movies

What makes Popcorn Pop?

Ah magical sound of corn popping – but what is it about this seed that explodes in fluffly flaky goodness?

Zea mays Everta

Popcorn is the species of corn called Zea mays everta with a very interesting characteristic. Unlike most grains, the pericarp or hull of the popcorn kernel is both hard and impervious to moisture. Inside this seed, the endosperm is made of a hard dense starch with a little bit of water and oil – ideally around 14% for good popping corn.

That little bit of water makes all the difference. When popcorn is heated that water turns to steam but it can’t escape the hard waterproff shell. As the temperature increases, the steam pressure builds and the starchy inside turn into a hot molten gel.. At around 356F (180C) the internal pressure is 135psi (930 kPa) – at this point the shell erupts and the molten starch expands quickly – rapidly cooling and forming an airy foam. This creates starch and protein polymers of that familar cruchy puff.

Mushroom (left) and Butterfly (right) popcorn flakes

Mushroom (left) and Butterfly (right) popcorn flakes

In the industry, there are two kinds of popcorn flakes – Butterfly flakes are irregularly shaped pieces with wings. This is considered to have a more pleasant mouth feel and is generally used for movie and everyday snacking popcorn. Mushroom flakes take on a more ball shape making them less frangile – often used for prepackaged popcorn and confectionary like caramel corn.

The Origins of Popcorn

Popcorn is perhaps oldest snack food known to man – with evidence of popcorn being found in the “bat cave” in Western New Mexico dating back to 3600 BC.

Bat Cave – Western New Mexico

The origins of popcorn as a species are not entirely clear, but it seems to go hand and hand with the domestication of maize by early Central and South American inhabitants.

In fact the English word “corn” is somewhat misleading. Corn originally meant whatever cereal plant was most used by a culture. To the English, corn was wheat, in Scotland and Ireland, corn was oats. When the European settlers came to the Americas – they found the inhabitants growing Indian Corn – or maize their dominant cereal plant.

Although European settlers in the new world encountered popcorn in central and South America, there is actually no evidence to suggest that popcorn was present at the first American Thanksgiving in Plymouth Massachusetts in 1621.

Instead Popcorn as we know it today would find its way to North American east coast as Valparaiso corn – brought up sailors and whalers from the Chilean port of Valparaiso recorded as early as 1820. Within a few years it came to be known by what we call it today “popcorn” – an Americanism that shortened the words popped corn. With the invention of wire poppers, popcorn spread quickly throughout the United States.

But it was industrialization that would cement popcorn in the American culinary heritage.


Chicago World’s Columbian Exposition 1893

At the World’s Columbian Expo in Chicago 1893, inventor Charles Cretors introduced the world’s first mobile popcorn machine – a simple steam engine attached to a peanut cart that cooked popcorn in a mixture of butter and lard.

Cretor's Popcorn Wagon (Version 2)

Cretor’s Popcorn Wagon (Version 2)

At the same expo F.W. Rueckheim introduced a molasses flavored “Candied Popcorn with Peanuts” – the first Caramel Corn. It was a bit too sticky for most people, so Rueckheim’s brother altered the recipe and packaged it a Cracker Jack in 1896.

Cracker Jack

With Cretor’s mobile popcorn machine and Cracker Jack, Popcorn became a staple of the American Social experience. By 1920s, popcorn was everywhere, at sporting events, circuses, parks, bars… everywhere except the movie theater.

The Courtship of Popcorn and the Movies

The movie palaces of the 1920s were fighting a PR battle with bawldry Nickelodeons. Movie theaters wanted to create an image of class and sophistication so they copied the style of traditional theaters – with sweeping architecture of grand lobbies and furnishing it with elegant crystal chandeliers and gorgeous carpets.

Roxy Theater Lobby, 1927

Roxy Theater Lobby, 1927

The movies were too refined and too good for the common man’s snack and owners didn’t want to deal with the mess and the aroma of popcorn in their immaculate halls.

But technology and economics change everything.

The most important shift in film technology was the addition of synchronized sound. After 1927, you could actually hear what the actors were saying on screen instead being required to read title cards.

This opened up the movies to brand new audiences – people who were illiterate and often poor and young children – audiences that wouldn’t really be attracted to the palatial setting of movie houses.

And then came the Great Depression. Many movie palaces went under and those that survived were clinging to dear life. Everyone in the movies were suffering… except for the street vendors who were proving there was a buttery goldmine in popcorn. Popcorn was a cheap luxury that people could still afford and it became the first snack smuggled under coats into the movie theater. In this dark time, you could actually make a living as a popcorn street vendor. An Oklahoma banker, who had lost his shirt in the stock market crash, resorted to selling popcorn in front of movie theater. Within a couple years, he made enough money to buy a house, a farm and a store.

Another example of the money in popcorn involves Kemmons Wilson, a young kid who dropped out of high school to support his family. He struck a deal with a Memphis movie theater to sell popcorn outside the theater to patrons. He bought a $50 machine on credit and began selling bags for 5 cents each. In not too much time he was making $40 to $50 dollars a week a lot of money in those times considering the movie theater was struggling to pull in $25. Jealous, the theater owner kicked Wilson out and moved into the popcorn business himself. This story does have a happy ending as Kemmons Wilson vowed to own his own theater so no one would ever take his popcorn machine away again and it was something he did years after he founded Holiday Inn.

Kemmons Wilson in front of his Holiday Inn

Kemmons Wilson in front of his Holiday Inn

The independent non-studio owned theaters were first on board the popcorn gravy train – R.J. McKenna – a manager that ran a chain of theaters in the west began selling popcorn inside the movie theater lobby where the buttery aroma boosted sales. By 1938 he was collecting over $200,000 in proceeds – for that money, who cares if the carpets got messed up. Another chain on the East coast experimented with popcorn only in there smaller theaters – keeping the nicest and fanciest theaters concessions free. Those that had popcorn were making a profit whereas the fancy theaters were dipping into the red.

Popcorn was literally saving the movie theater business – so much so that a Depression-era entrepreneur once gave this bit of advice:

Find a good place to sell popcorn, and build a movie theater around it

Popcorn Comes Home

Popcorn continued its growing in American Pop culture especially during World War 2 when sugar rations made candy and chocolate scarce. But popcorn, like the movies would face a serious challenger in the new entertainment technology of the 1950s: Television.

Television was the last straw in a crumbling studio system in the late forties and fifties. Movie attendance dropped as much as 50% inside the decade – along with it popcorn sales.

The problem with popcorn was it was hard to make at home and in small servings. But as the movies turned to new technology to lure audiences back into theaters, the popcorn industry turned to technology to make popcorn at home. Brands like EZ pop in 1955 and Jiffy Pop in 1959 sold packaged unpopped kernels in disposable aluminum pans that would expand during cooking. Despite patent violation lawsuits, Jiffy Pop would go on to become the standard for home cooked popcorn for a generation.

But it was another piece of technology that would make popcorn the perfect companion for a night in with a movie: The Microwave Oven.

Raytheon Manufacturing Corporation was a company based out of Massachusetts that made radio tubes for consumer use. During World War II, the British approached them to mass produce an electronic component called a magnetron to be used in their secret weapon – RADAR. Raytheon ended up producing over 80% of all magnetrons used by the Allied Forces, shooting their income from $6 million a year in 1942 up to $173 million by the War’s end. But the executives faced a serious problem: what would they do with all these magnetrons once hostilities cease?

Percy Spencer

Percy Spencer

In late 1945, a Raytheon Engineer and Inventor named Percy Spencer brought a patent attorney into the lab for a demonstration. He set up a microwave tube and dropped a kernel of popcorn in front of the wave guide. It popped – creating the world’s first microwaved popcorn. Within two years the first commercially produced microwave oven was introduced – standing about 6 feet tall, weighed 750 lbs, and costing between $2,000 and $3,000.


Raytheon’s first commercially produced Microwave Oven

Perhaps a bit big and expensive for most families but a couple of decades of refinement would eventually result in counter sized models and the microwave popcorn boom would take hold in the 1980s – just in time for popularization of premium cable and watch-at-home movie technologies like VHS, Beta and LaserDisc.

The Marriage of Popcorn and Movies

(500) Days of Summer

(500) Days of Summer

For some, the movie going experience is simply incomplete without a bucket of buttery yellow popcorn. The tie is not only a personal and cultural connection – it’s actually an economic one as well. Popcorn pulled movie theaters from bankruptcy during the Great Depression and it still accounts for as much as half of the profit generated by a movie theaters today -more so than the actual ticket price which has to be shared with the movie studios distributors. By charging that outrageous and frankly insane mark-up we pay at the concessions, the movie theater can keep ticket prices lower and make their profit selling snacks and treats. Ultimately it is this little puff of air and starch that is responsible for keeping movies in business. For without popcorn, there simply would be no theaters, and perhaps no movies -at least not the way we know them. Whether you partake or not, know that this simple ancient snack help make film and filmmaking possible.


The Science and History of Popcorn Quiz