[♪ INTRO]
Oh, hey there!
Tonight, we’re hosting a movie night for all of our friends!
We love movie night!
Especially because we get to enjoy one of my favorite snacks: popcorn!
[Squeaks squeaks]
It’s so light and fluffy and crunchy …
[Squeaks squeaks]
Oh! How did this hard seed get in the bowl?
That’s just some unpopped popcorn!
[Squeaks squeaks]
Well you see, all popcorn starts out as this small, hard seed, called a kernel!
[Squeaks squeaks]
Yes, a seed!
You see, popcorn is just a special type of corn – it even grows on a corn cob,
just like those ears of sweet corn that you enjoy munching on in the fall!
The pieces of corn on the cob are the seeds of the corn plant!
Once the ears of corn are fully grown, we dry the seeds so that most of the water is gone.
Then, people can pop those seeds into yummy popcorn!
But we still have to do a little bit of work to turn that hard seed into a fluffy snack!
Hey Squeaks, would you like to make some popcorn with me,
so we can see how the popcorn changes?
[Squeaks squeaks]
Alright! Let’s pop some corn!
This is an air popper, and I use it to make popcorn!
You can also make popcorn on the stove using a pan and a little bit of cooking oil!
Now we need some popcorn kernels.
Let’s measure out about half of a cup of kernels.
How much popcorn do you think we’ll get from just these little seeds, Squeaks?
[Squeaks squeaks]
I think you’ll be surprised!
Here, let’s take a closer look at some kernels.
What else do you notice about them?
[Squeaks squeaks]
You’re right, they’re pretty hard, even though popcorn is soft and fluffy!
This unpopped corn is much too hard for us to eat right now.
But that hardness is part of the secret behind its ability to pop!!
[Squeaks squeaks]
You see, inside every popcorn kernel is a little bit of water.
[Squeaks squeaks]
Yes, even though it went through a long drying process after it was picked
from the field, a little bit of water stays behind inside the seed.
And that little bit of water is super important!
That’s because when water gets heated up, like when we heat up this popcorn,
it starts to take up more space, or expand.
In fact, as the water heats up, it starts to change.
Do you know what happens to really hot water, Squeaks?
[Squeaks squeaks]
Yes! It turns into steam.
The steam is different from liquid water – it’s what we call a gas.
If we put a kettle or pot of water on the stove, we can see steam rising from it.
That steam is actually very hot water in the form of a gas!
But the steam in the popcorn kernel has nowhere to go, because that hard shell
is keeping it trapped inside.
Which means it keeps growing and pushing on the sides of the popcorn kernel.
It gets bigger and bigger inside the kernel, until that hard shell just can’t take it
any longer and bursts open.
And there it goes!
See how those hard kernels turned into white, fluffy popcorn?
And oh wow, look how much of the bowl they’re taking up!!
It looked like such a tiny amount of popcorn when we first poured it
in the popper, didn’t it?
But now this popcorn fills it up almost to the brim!
[Squeaks squeaks]
Why is each piece of popcorn so much bigger than the tiny kernels we poured in?
That’s a great question, Squeaks!
The reason is because the inside of the seed got bigger too.
Besides water, the insides of the seed contain food for that seed.
That food is there to help it grow if it were ever to be planted in the ground.
We call that food starch.
[Squeaks squeaks]
Yes, it’s a little like the sugar that maple trees use for food!
Both things are food for the plant.
The starch also gets bigger when it gets hot.
Just like the water inside the seed!
Once the popcorn pops open, the starch comes pouring out and turns into
a delicious, fluffy snack for us to enjoy.
Isn’t it amazing how much popcorn changes just by heating it up?
Of course, it never un-pops, even if you let it cool back down again.
Some things do change when you heat them, then change back again
when they cool down.
Like, that steam we talked about can become water again!
But once it bursts out of the popcorn, the popcorn stays popped.
And yummy!
Wasn’t that fun, Squeaks?
[Squeaks squeaks]
Sometimes, science is not only fun but also delicious!
Can you think of other things that change when they’re heated?
Do they stay the same when they cool down, or do they go back
to the way they were?
Thanks for joining us today.
If you want to keep having fun with me, Squeaks, and all of our friends,
hit the subscribe button, and we’ll see you next time here at the Fort.
[Squeaks squeaks]
[♪ OUTRO]