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Oh, hey there! Tonight, we’re hosting a movie night for all of our friends!
哦,嘿! 今晚，我们要为所有的朋友举办一场电影之夜!
We love movie night!
我们喜欢电影之夜!
Especially because we get to enjoy one of my favorite snacks: popcorn!
尤其是因为我们可以享受我最喜欢的零食之一:爆米花!
It’s so light and fluffy and crunchy …
又轻盈又蓬松又松脆……
Oh! How did this hard seed get in the bowl？
哦! 这些坚硬的种子是怎么进入碗里的?
That’s just some unpopped popcorn!
那只是一些未爆开的的爆米花!
Well you see, all popcorn starts out as this small, hard seed, called a kernel!
你看，所有的爆米花一开始都是这种又小又硬的种子，叫做玉米粒!
Yes, a seed!
是的,一颗种子!
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!
你看，爆米花只是一种特殊的玉米——它长在玉米棒子上，就像那些你喜欢在秋天咀嚼的甜玉米穗!
The pieces of corn on the cob are the seeds of the corn plant!
玉米棒上的玉米粒就是玉米的种子!
Once the ears of corn are fully grown, we dry the seeds so that most of the water is gone.
一旦玉米穗完全长熟，我们就把种子晾干，这样大部分水分就没有了。
Then, people can pop those seeds into yummy popcorn!
然后，人们可以把这些种子做成美味的爆米花!
But we still have to do a little bit of work to turn that hard seed into a fluffy snack!
但我们还需要做一些工作，把坚硬的种子变成蓬松的零食!
Hey Squeaks, would you like to make some popcorn with me, so we can see how the popcorn changes？
嘿，吱吱，你愿意和我一起做一些爆米花吗?这样我们就可以看到爆米花是如何变化的?
Alright! Let’s pop some corn!
好! 让我们将这些玉米粒爆开吧!
This is an air popper, and I use it to make popcorn!
这是一个爆米花机，我用它来做爆米花!
You can also make popcorn on the stove using a pan and a little bit of cooking oil!
你也可以用平底锅和一点食用油在炉子上做爆米花!
Now we need some popcorn kernels.
现在我们需要一些玉米粒。
Let’s measure out about half of a cup of kernels.
让我们量出大约半杯玉米粒。
How much popcorn do you think we’ll get from just these little seeds, Squeaks？
吱吱，你认为这些玉米粒能给我们带来多少爆米花?
I think you’ll be surprised!
我想你会大吃一惊的!
Here, let’s take a closer look at some kernels.
在这里，让我们仔细观察玉米粒。
What else do you notice about them？
你还注意到了什么？
You’re right, they’re pretty hard, even though popcorn is soft and fluffy!
你说得对，虽然爆米花又松软又蓬松，但它们确实很硬!
This unpopped corn is much too hard for us to eat right now.
这些未爆开的玉米现在对我们来说太难吃了。
But that hardness is part of the secret behind its ability to pop!!
但这种硬度是爆米花爆开背后的秘密的一部分!!
You see, inside every popcorn kernel is a little bit of water.
你看，每个爆米花仁里面都有一点水。
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.
是的，即使从地里采摘后经过了很长时间的干燥过程，种子里仍然会留有一点水分。
And that little bit of water is super important!
这一点点水是非常重要的!
That’s because when water gets heated up, like when we heat up this popcorn, it starts to take up more space, or expand.
这是因为当水被加热时，就像我们加热爆米花一样，它开始占据更多的空间，或者膨胀。
In fact, as the water heats up, it starts to change.
事实上，当水加热时，爆米花开始发生变化。
Do you know what happens to really hot water, Squeaks？
吱吱，你知道真正的热水会怎么样吗?
Yes! It turns into steam.
是的! 水变成了蒸汽。
The steam is different from liquid water – it’s what we call a gas.
蒸汽与液态水不同，它是我们所说的气体。
If we put a kettle or pot of water on the stove, we can see steam rising from it.
如果我们把一个水壶或一壶水放在炉子上，我们可以看到蒸汽从它水壶上面升起来。
That steam is actually very hot water in the form of a gas!
蒸汽实际上是非常热的水，它以气体的形式存在!
But the steam in the popcorn kernel has nowhere to go, because that hard shell is keeping it trapped inside.
但是爆米花内核中的蒸汽无处可去，因为坚硬的外壳将它困在里面。
Which means it keeps growing and pushing on the sides of the popcorn kernel.
这意味着蒸汽会不断扩大，挤压玉米粒的边缘。
It gets bigger and bigger inside the kernel, until that hard shell just can’t take it any longer and bursts open.
它在玉米粒里变得越来越大，直到坚硬的外壳再也承受不了它，爆裂开来。
And there it goes!
就是这样!
See how those hard kernels turned into white, fluffy popcorn？
看到那些坚硬的玉米粒是如何变成白色蓬松的爆米花的了吗?
And oh wow, look how much of the bowl they’re taking up!!
哦，哇，看看他们占了多少碗!!
It looked like such a tiny amount of popcorn when we first poured it in the popper, didn’t it？
当我们先把它倒进爆米花机的时候，它看起来就像很小的爆米花，不是吗？
But now this popcorn fills it up almost to the brim!
但是现在爆米花几乎把它填满了!
Why is each piece of popcorn so much bigger than the tiny kernels we poured in？
为什么每一粒爆米花都比我们倒进去的小玉米粒大那么多?
That’s a great question, Squeaks!
吱吱，这是个好问题!
The reason is because the inside of the seed got bigger too.
这是因为种子的内部也变大了。
Besides water, the insides of the seed contain food for that seed.
除了水之外，种子的内部还含有种子所需的食物。
That food is there to help it grow if it were ever to be planted in the ground.
如果种子被种植在土地里，食物就会帮助它成长。
We call that food starch.
我们称之为食物淀粉。
Yes, it’s a little like the sugar that maple trees use for food!
是的，它有点像枫树用作食物的糖!
Both things are food for the plant.
这两种东西都是植物的食物。
The starch also gets bigger when it gets hot.
淀粉加热后也会变大。
Just like the water inside the seed!
就像种子里面的水一样!
Once the popcorn pops open, the starch comes pouring out and turns into a delicious, fluffy snack for us to enjoy.
一旦爆米花爆开，淀粉就会流出来，变成美味、蓬松的小吃供我们享用。
Isn’t it amazing how much popcorn changes just by heating it up？
爆米花只要加热就会发生很多变化，这不是很神奇吗?
Of course, it never un-pops, even if you let it cool back down again.
当然，即使你让它再次冷却下来，它也不会变成原来的大小。
Some things do change when you heat them, then change back again when they cool down.
有些东西在你加热的时候会变，然后在它们冷却的时候又变回来。
Like, that steam we talked about can become water again!
比如，我们说过的蒸汽可以再次变成水!
But once it bursts out of the popcorn, the popcorn stays popped.
但玉米粒一旦变成爆米花，爆米花就会一直蓬松下去。
And yummy!
好美味!
Wasn’t that fun, Squeaks？
是不是很有趣，吱吱?
Sometimes, science is not only fun but also delicious!
有时候，科学不仅有趣，而且美味!
Can you think of other things that change when they’re heated？
你还能想到其他东西在加热时会发生变化吗?
Do they stay the same when they cool down, or do they go back to the way they were？
它们冷却后是保持不变，还是回到原来的状态?
Thanks for joining us today.
感谢您今天的观看。
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.
如果你想继续和我、吱吱以及我们所有的朋友一起玩，请点击订阅按钮，我们下次在福特堡见。
