Question

Why cooking food is an irrevesible change

Answer 1

Cooking food is an irreversible change because we can't convert food into its original form or once it gets cooked we can't get the original state.

Answer 2

Because you cannot get or convert the cooked food to its first form.
Ex:If you boil the rice in a cooker after that you cannot convert it helps into the rice when it was not cooked.