How does ice get into sealed packages in my freezer?

Other than in the ice cube tray, there’s no ice growing inside my freezer. But whenever I keep sealed plastic packages/bags of frozen food in there for a few months, ice flakes start to form inside them, and over time more and more ice shows up.

There was no ice in these sealed packages when I first put them in my freezer. Most are factory-sealed. Like a little individually-packaged chicken sandwich or burger or whatever. Even frozen TV dinners in a plastic tray sealed under plastic wrap and also packaged inside a sealed cardboard box get ice growing in them after 6-8 weeks. An unopened, factory-sealed bag of frozen vegetables will turn to a big chunk of ice if I leave it in my freezer for a few months.

I can’t figure out where this ice comes from. Surely there’s no significant humidity in my freezer, and any humidity that gets in when I open the freezer door shouldn’t be able to get through the plastic into these sealed packages. Again, I don’t have any ice growing inside my freezer except inside all these sealed packages of frozen food. How does this happen, and is there anything i can do to stop it?


It’s moisture from the food.

Ice will evaporate even at freezer temps. Ever find an old ice cube in the back that’s reduced to a mere sliver?

Just like freeze drying process except the ice is still in the package in your case. Google “freezer burn”.

Like others said, it’s coming out of the food. As it comes out of the food it re-condenses in surfaces inside the package. The reason you don’t have ice in other places inside your freezer is two-fold. 1)Each time you open your freezer it escapes and 2)You DO, it’s on the coils, which then get defrosted, turned into water and drip down to a tray under the freezer to evaporate into the room.

Go look at an old freezer or ask mom/grandma about manually defrosting the freezer every few months when there was so much ice built up they couldn’t fit anymore food in it.

quantum tunneling of water molecules.

or maybe it’s coming from the food. moisture over time will equally distribute through the package. while the food item might still be warm it will be drawn to the cold inside surface of the food package, you can refrigerate the item before freezing to minimize this.

ok. thanks.

My related question: I’ve noticed exactly this too, regularly. Freezers have a characteristically “freezer” odor in them (freon? or other refrigerant?), and it’s in that ice too. Yuck. Is it best to rinse this off of frozen food before cooking?

With most frozen vegs, at least, I do. I pour vegs into bowl, fill with hot water (which immediately becomes cool water), drain, then repeat with cold tap water, drain again, then cook. Gotta wash away all those nasty vitamins and minerals!

No, really, I’m sure that doesn’t actually wash away any significant amount of vitamins and minerals. But some frozen vegs come with some kind of seasoning coating them, and that does get washed away. Those, I don’t rinse. Other kinds of frozen foods aren’t readily rinseable also.

So, what about cooking food with all that freezer ice included? How yucky is that really?

It’s not freon (at least it shouldn’t be*). It’s just a combination of everything in there. You’ll probably do yourself a favor by pulling everything out and cleaning your freezer. Toss the stuff you don’t need and defrost it if the sides and racks are full of ice. If that doesn’t help, Baking Soda really does help. At work, we use them in our seafood freezer (in the store). Get the ones where the sides peel off so they don’t spill, put them in a place where they’ll get some air movement and change them a few times a year. I know we need to change them when the freezer starts smelling fishy again.
*Any freon that escapes from the system would dissipate VERY quickly and with how small of a system a home fridge has (about a quarter of a pound) even a small leak would mean losing all the refrigerant pretty quickly. Also, you’d probably get it in the fridge as well.

To sublimate is sublime.