How does freezer burn affect meat?!
Answers:
What you're describing (small icicles on pre-made burger patties) is just freezer snow, freezer burn would change the color of the meat. Both cases are completely safe to consume.
While a food with freezer burn is safe to eat, the quality is lower. You can cut away freezer burn spots either before or after cooking. If a food is heavily freezer-burned, it may be desirable to discard it for quality reasons.
http://wiki.answers.com/Q/Can_you_eat_meat_that_is_freezer_burn
Freezer burn does not make food unsafe, merely dry in spots. It appears as grayish-brown leathery spots and is caused by air coming in contact with the surface of the food.
you CAN still eat it but it won't taste as good ... :/