Why do dumplings sink when frozen but float when cooked?

Question

I noticed whenever I boil frozen dumplings they sink to the bottom at the beginning but once they’re ready to eat they float up. How do we know the meat inside is cooked once they float or vice versa

In: Chemistry

Answer 1

Steam. As the filling heats up, the wrapper traps the steam, and that causes it to float, because steam is less dense than water.