Taste Testing

Why does everything have to go into the mouth except for new food items? We've been trying all kinds of new self-feeding things and the kids seem to be very cautious about putting them in their mouths and tasting them. This isn't the case though with every toy, stuffed animal, piece of clothing, etc. that they come across. They like to touch, poke at and throw the new foods onto the floor, but it takes a while for them to warm to the idea of eating them.