What should I do if I see ice crystals or dry patches on a frozen entrée I just purchased?

Discard it. Ice crystals or dry patches are a sign the cold chain has been broken. Chances are the entrée was allowed to thaw on the back of a distributor's truck, at the supermarket, or elsewhere. The entrée won't taste good and, depending on how long it was allowed to thaw, may have had time for pathogens to grow to harmful levels. Under those conditions, preservative-free entrees are even more vulnerable because they are subject to a greater rates of microbial growth than entrees that contain preservatives. Refreezing the entree will inactivate the microbes, but the damage may already be done even if the entrees are subsequently cooked.
 
Source(s):
Webmd.com "The Best Frozen Dinners"