Why does heat make popcorn's corn pop? And How?!
Answers: I always enjoy putting microwave popcorns into the microwave when I sit down for a long battle between the TV and myself, ussually the remote joins in on the fight but there were occasions where the remote just dissapears. As I was poping my popcorn, my 4 year old little sister asked me a curious question that has got me thinking trough a nice movie of sponge-bob (my sister's) that I should of watched along with her. So why does heat pop popcorns?
It seems there is a drop of moisture that gets trapped inside each and every kernal. It closes before this drys up.
So when it gets hot it creates steam and the pressure builds until it pops out. Like pinching a pimple only it does serious damage to the kernal. In essence blowing it up.
Some kernals of hard red wheat does that also. I have poped it before and it makes a crunchy kernal that without popping would be impossible to eat.
There is a little moisture in each kernel. When the moisture / water gets hot enough, the kernel 'explodes' and transforms itself into a piece of popcorn.