Yes. This is too often a sign that the frozen food has thawed to some extent at least once before we saw it. The source of the frost is usually moisture that has escaped from the food inside the package. But even if the ice crystals are caused by moisture from another package, its existence portends deterioration, because if one package inside a shipping container has thawed, then chances are that some of the contiguous packages have also.
Sometimes thawing occurs in the store's display unit. Research in several dozen supermarkets indicates that the surface temperatures of the topmost frozen-food packages in open display units are sometimes about 32o
F. It is also observed that a similar problem for refrigerated items like meat and milk that are stored in open display units. The temperatures of the topmost (or foremost) refrigerated packages are occasionally higher than they should be. This condition reduces storage life and probably creates a health hazard now and then. When buying, remember to select deep.
** Asian Recipes