Burnt in the Freezer

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It may be a misnomer, but people often refer to damage caused by extreme cold as a "burn."  This is probably because when we touch very cold things like dry ice, (solidified carbon dioxide), or go out on a very cold day and get frostbite, it is as painful as a burn.  The pain is caused by water in the skin freezing and crystallizing.

The same thing can happen to food in the freezer.  If meat is left in the freezer without an air tight wrapping, the millions of water molecules within the food form ice crystals.  Once formed, the ice crystals sublimate, that is they escape from the food in the solid state, allowing the ice crystals to migrate to the coldest place in the freezer – usually the side.

When ice crystals escape, the food dehydrates, that is, it dries out and shrivels up.  Meat turns brown when this happens, looking as if it has been burned.  As the water molecules escape from the meat, oxygen molecules seep in, dulling the red colour and modifying the flavour.

The longer the items are stored in the freezer, the greater the number of water molecules that sneak out of the frozen food.  The obvious solution is to tightly wrap the food so that no water molecules can escape, and no oxygen molecules can enter.

So next time you're questioning some unappetizing looking frozen food, remember that although freezer burned foods are safe to eat, they will taste and look better if you store them in airtight containers.