I used to freeze mine in plastic tubs,had to ship it in.
I just took out a tub at a time, about a weeks worth.
I have fed it too them right out of the freezer, great summer treat.Then I just let it thaw on the shelf.
I have never seen any condinsation on the tub, it was clean plastic so it did get cloudy,but never ran off.I guess there is no moisture in the feed so if it's airtight none can get in. Well min.
Just check the "snap factor" LOL best way I could think of to describe it. Crack some fresh so you know what it should feel like. Then when it thaws out do the same and see if it's softer than before.
If it's stale they probebely won't eat it anyway.
Worth checking it all out though before you freeze 6 months supply. ::nod::Not all feeds are the same.