If matter expands when heated, why does most food shrink when being cooked?

Question

If matter expands when heated, why does most food shrink when being cooked?

In: 2

Answer 1

Most food has water in it, and some of that water is boiled away when you heat it- that’s most of the shrinkage. That’s why a hamburger patty or a roasted vegetable is going to shrink when you cook it.

Then think about pasta or rice. Those increase in size when you cook them- because they start dry and then absorb more water.