the only way it's going to mold is if you leave it in there for like 24 hours(and never breathe it). it only takes about 4-8 hours to retain moisture. if your friends molded in less than 24 hours, it's because he put a really juicy piece of fruit in there.
you only want small pieces of peel which doesn't have a lot of moisture in the first place.
you only want small pieces of peel which doesn't have a lot of moisture in the first place.