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Freezer Burn Explained!

You did your best to wrap up that fresh piece of steak before putting it in the freezer. You did your best, but the plastic wrap got all tangled up and, somehow, you missed a corner. A week later most of the steak looks fine, but that corner is all shriveled and rubbery looking. It's got a serious case of freezer burn.

What It Means...

What does "freezer burn" mean? The exposed steak *does* look kind of darker and shrunken, but has it been burnt? Is there some kind of magical fire that breaks out in our freezers, but only burns things that aren't well wrapped?

Actually, freezer burn isn't a burn at all. It's dehydration. There's lots of water in the foods we eat. That's why we can freeze them in the first place--the water in your steak turns to ice, and you say that the steak is frozen. The air inside your freezer, however, doesn't have lots of water. It's very dry.

Ice is dry

Any time you expose ice to dry, cold air, a process called sublimation begins. This is ice's version of evaporation--the frozen water turns directly to vapor, without going through a liquid phase, and drifts away in the freezer fan's breeze. When this happens to exposed food, it dries out very quickly and gets all rubbery.

You'll want to throw away that dried out part, although the rest of the steak should still be fine to eat. The best way to prevent freezer burn is to use plastic bags or wrap especially designed for freezers. These keep your food safe from that cold, drying air.

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