What is Freezer Burn?

4 minutes

You put food in the freezer to prolong its life and prevent it from going bad. You’d think a freezer was a safe space, then? Unfortunately, there’s one major problem with storing food in the freezer, and that is freezer burn. So, what is it?

What Causes Freezer Burn?

Freezer burn is a condition that occurs when frozen food is exposed to air. This is usually a result of food not being securely wrapped or sealed properly in airtight containers.

Here’s a detailed explanation of the process:

1. Dehydration
   Freezer burn begins with sublimation when solid ice transforms directly into water vapour without first becoming liquid. This process happens in freezers, especially when the temperature fluctuates and isn’t consistently at 0°F / -18°C or below.
2. Oxidation
   Along with dehydration, exposure to air leads to oxidation in the food. Oxidation is a reaction that happens when oxygen interacts with the food on a molecular level. This can alter the chemical structure of the food’s molecules.
3. Ice Crystals Formation
   The dehydration and oxidation processes can cause the formation of ice crystals on the surface of the food. The water inside the food is drawn out to the surface and then frozen.

What Does Freezer Burn Look Like?

Several noticeable changes in the appearance and texture of food can identify freezer burn:

1. Colour Changes
   One of the most noticeable signs of freezer burn is discolouration. The affected areas often appear greyish or brownish. This is especially noticeable on meats, where bright red beef, for instance, can turn a dull brown in patches where freezer burn has occurred.

2. Dry Spots or Patches
   Freezer burn can cause certain areas of the food to look dried out or dehydrated. These spots may appear rough, leathery, or slightly wrinkled compared to the rest of the food.
3. Ice Crystals
   The presence of ice crystals or a frosty layer on the surface of the food is a common sign of freezer burn. This frosty appearance comes from moisture escaping the food and freezing on its surface.

4. Texture Changes
   Although texture changes might be more difficult to spot until the food is thawed, freezer-burned areas can have a tough, leathery texture compared to unaffected areas.

What Does Freezer Burn Taste Like?

Freezer burn can significantly affect the taste of food. The areas of food that have been freezer-burned might taste bland or lack the original flavour of the food.

This is because freezer burn dehydrates the food, and water is a major carrier of taste in food.

In addition to a lack of flavour, freezer-burned food can sometimes take on an off or unusual taste. This can be described as a slightly “off” flavour or even a somewhat sour, metallic, or cardboard-like taste.

This taste can occur due to oxidation and dehydration during freezer burn.

Freezer-burned meat may also taste a bit more gamey or have an off-putting sweetness. The change in flavour can be more noticeable in high-fat foods, as fats can become rancid over time when exposed to air.

However, the taste of freezer burn can be hard to describe precisely because it depends on the type of food, the degree of freezer burn, and individual taste perception. The best way to prevent your food from acquiring this unpleasant taste is to protect it from air exposure and consume it within a reasonable timeframe.

Unfortunately, getting rid of the taste of freezer burn is not particularly easy without ruining the frozen food. It would involve cutting off the chunk of freezer burn and then serving the food with a strong sauce to mask the flavour.

How Do You Prevent Freezer Burn?

Freezer burn can be a real nuisance, but there are several strategies you can use to prevent it:

1. Proper Packaging
   This is one of the most important steps in preventing freezer burn. Food should be stored in containers or bags designed for freezer storage. These are typically thicker than regular storage materials, providing a better barrier against moisture loss.
2. Portioning
   By storing foods in serving or meal-sized portions, you can avoid exposing all your food to air each time you need to take something out of the container.
3. Freezer Temperature
   Keep your freezer temperature at 0°F / -18°C or below. Fluctuating temperatures can cause the freeze-thaw cycle that leads to freezer burn.
4. Avoid Keeping Foods in or Near the Door
   The temperature of the freezer door fluctuates the most, which can contribute to freezer burn. It’s better to store foods in the main part of the freezer where the temperature is more stable.
5. Don’t Keep Foods in the Freezer for Too Long
   Even under perfect conditions, foods stored in the freezer for a very long time can eventually develop freezer burn. Try to use foods within their recommended freezer storage times.
6. Use Vacuum Sealers
   If you freeze foods often, a vacuum sealer can be a good investment. These machines remove almost all the air from packaging, significantly reducing the risk of freezer burn.
7. Repackage Store-bought Frozen Foods
   If you buy frozen food in a cardboard box, consider removing the food from the box and placing it in a sealable freezer bag. Cardboard doesn’t provide a great barrier against air and moisture.