Why does popcorn pop?

Answer 1

The physics of popcorn popping are quite interesting. In any popcorn popper you use (stove top, microwave or hot air) it works the same way:

• The popcorn kernel is a tough coated seed with a damp internal core of starchy material
• As it is heated the water in the inner part would like to boil but the pressure and containment of the kernel's coat prevents it from doing so.
• Eventually the pressure on the inside gets high enough to rupture the tough coat
• The sudden release of pressure lets the water that was way over boiling point suddenly flash into steam (and taking up a lot more volume in the process)
• This expanding steam froths up the starch into the white popped corn then evaporates into the air

there is water inside that makes it expand
There is a certain amount of moisture in each kernel. When the moisture get heated it bursts open and makes an explosion which turns the hard outter shell inside out and the starch turns into the puffy part of the popcorn.
When the popcorn goes into the microwave, it gets heated up. The water inside begins to boil, and pressure begins to build inside the kernel. Eventually, there is so much pressure, it tears itself inside out, through it's own shell, leaving the heated starch (outside of popcorn we can see) behind.
Popcorn pops because the water inside the kennels heats up and bgins to steam. If the shell has no cracks in it the steam will not come out and it then becoms a pressure cooker inside the shell. The pressure then becomes to much for the shell and it pops into popcorn. Usually around 135 psi.

Answer 2

Because the corn always overheat and then it pops because it fully