We belong to the fairy world, not this one, and no mortal has ever tasted our flesh. Now a queen has come along and she is determined to get at us. She tried to climb the garden wall, and when her ladders didn’t reach, she went to see our mistress, the Old Fairy. Heaven knows what the queen will bargain will make to get a taste of us. She’d sell her own daughter, we suppose!

Fruit of the Fairy Trees in The White Cat, Blue Fairy Book