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Question What is "freezer burn?"


The outcome of frozen food losing its moisture as a result of poor wrapping.

Ask the man who repairs one, and he’ll tell you to turn the freeze control back to normal after quick-freezing ice-cubes or ice cream. United States Office for Emergency Management, 1942. Prints and Photographs Division, Library of Congress.

Have you ever wondered what happened to a steak in the freezer that looks discolored and parched? It is covered in frost and there are dry spots on the meat tissue. It looked fine when you froze it a few months ago. What caused this transformation?

When food is frozen as a method of preservation, thousands and thousands of water molecules within the steak form ice crystals. These water molecules prefer the most hospitable environment- the coldest place in your freezer. The molecules migrate from the steak to the coldest place they can find, which is often the side of your freezer. The loss of these water molecules causes the steak to become dehydrated. The end result is freezer burn.

So why did this happen?

  • Most likely, your food was not tightly wrapped enabling water molecules to escape and seek a better location.
  • Also, freezer burn is likely to occur for items stored in the freezer too long. There is a limit to how long items should be stored in the freezer. Sooner or later the water molecules will find their way out of the frozen food to a colder place in your freezer. (See Refrigerator & Freezer Storage Chart listed in Web resources)
  • The temperature of your freezer may have been above 0 degrees F. Freezer burn will set in from fluctuating temperatures above 0 degrees F.
Conservation of durable goods. Old Man Winter comes to the refrigerator. This unfortunate freezing compartment is lumbering along day and night, coated with excess frost. United States Office of War Information, 1942. Prints and Photographs Division, Library of Congress.

When water molecules escape from your frozen food, it is also possible for oxygen molecules to seep in. The oxygen molecules can dull the color and modify the flavor of your frozen product.

Food that has freezer burn is safe to eat, but you may find the texture and taste not to your liking. Listed below are Web sites that provide freezing tips so that your frozen food will be in first-rate condition to serve to your friends and family.

Wrapping up cuts of meat which will be put in freezing room, cold storage lockers. Casselton, North Dakota. Prints and Photographs Division, Library of Congress.

Published: 11/19/2019. Author: Science Reference Section, Library of Congress

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