Why popcorn pops: a pea-sized pressure cooker that gives way at 180 °C
30seconds
A popcorn kernel is a pressure cooker the size of a pea. Its tough hull seals in about 14% water, so as the pan heats, the water cannot boil away and the pressure builds.
At around 180 °C the steam reaches roughly 10 atmospheres and the hull gives way. The starch inside flashes into a foam that sets as the white flake you eat. Drag the heat up and watch which kernels go first.
Deep dive · 3 min
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