If you’re chiefly in charge of food preparation in your house, the freezer can be a lifesaver. Whether it saves you the time of going to the supermarket to pick up ingredients or saves you from having to do anything other than defrost and serve, it’s one of life’s greatest kitchen commodities.

“You can freeze almost anything,” says Zahraa Qassim, a dietitian with Eat Right Ontario. “Usually, frozen foods are safe indefinitely, but after a while, they won’t taste as good once you thaw and cook them.”

The ideal conditions for freezing food, whether it’s raw or cooked, is 0 F (or -18 C), although Qassim says raw food lasts longer in a frozen state. But proper storage is just as important as the temperature.

“Make sure the food is stored in freezer bags, and let any excess air out of the bag before sealing,” she says.

Despite all of your best efforts, however, sometimes even food that’s been frozen at the right time using the right techniques won’t be as flavourful after a certain amount of time. While Qassim says the food will be safe to eat, the flavour quality will be compromised.

Look for the following signs in your frozen foods to determine if they’re still good.

It’s freezer burnt

We all know freezer burn can be a food killer — how many tubs of ice cream have succumbed to it? But aside from its telltale crystalline peaks, it can look different on meat.

“Freezer burnt beef has dry spots on it that look greyish or brown,” Qassim says. “It’s caused by air coming in contact with the surface of the meat. It’s still safe to eat, but the quality and taste won’t be great.”

Proteins that are discoloured, including pork, fish and chicken, will be dry and lacking in flavour after cooking.

There’s a change in texture

If your vegetables, which were once vibrant and crisp-looking, now appear dull and slimy, they won’t taste great, although they’ll be safe for consumption. If, however, you’ve defrosted chicken and find a similar texture, discard it.

It smells weird

In addition to preventing freezer burn and moisture loss, proper storage in an air-tight bag or container will also prevent the passage of smells from one type of food to another. But if you’ve defrosted something and it smells off, it’s probably not worth cooking.

You can’t remember when you froze it

It’s easy to take something that’s been sitting in the refrigerator for several days and throw it in the freezer with the intention of saving it for another day, but it becomes a problem when you do this repeatedly and don’t label the package. If you find yourself digging through your freezer and looking quizzically at a frosted package with undistinguishable contents, just toss it.

It’s sitting in a frozen puddle

Have you had to yank the freezer bag out of an icy puddle that formed around it? Go ahead and discard that item. Chances are, it started to thaw at some point, which means the temperature of the food was compromised and it may no longer be safe to eat.

The packaging is ripped

If you’re taking out a package of meat, fish or vegetables and find that the packaging is ripped, there’s a good chance that the food was freezer burnt in the process. You can cut off the parts that are freezer burnt or if there’s too much damage, throw it away.

How to safely thaw food

While most things can be safely frozen, there are specific rules regarding the thawing process to ensure your food is safe to eat.

“Bacteria grows rapidly in the four to 60 C range, which we call the ‘danger zone,'” Qassim says. “Anything that has been left at this temperature for over two hours can cause illness.”

For this reason, experts say to never thaw anything at room temperature on your kitchen counter, except for bread and baked goods.

The top three methods for thawing food are: in the refrigerator, in cold water or by microwaving on the “thaw” setting.

“It’s very important to cook food immediately after it’s been thawed in the microwave, however, because this method can partially cook the food putting it in the ‘danger zone’ right away,” Qassim says. “Cook it immediately to make sure no bacteria will grow.”

For a list of foods that can be frozen and their ideal freezer time, consult the storage chart of the Canadian Partnership for Food Safety Education.