Why does putting a piece of bread in a container of cookies allow the cookies to stay soft while only the piece of bread hardens?

Question

My baker friend taught me this trick. I’m mystified and don’t understand how it works.

In: Other

Answer 1

The air will essentially suck out some of the moisture of the cookies and bread to equilibrate somewhat over time–meaning they go stale. Bread has a lot of surface area, so the moisture gets pulled out of that first, and it equilibrates much faster *without* pulling moisture out of the cookies nearly so much.