How Do I Know When Salmon Has Gone Bad?

When you buy fresh salmon, make sure you plan to use it within a day or two, or else store it in the freezer.
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You know when salmon has gone bad if it smells sour, rancid, fishy or like ammonia. If it smells like this when it's raw, the smell is likely to get stronger when it's cooked. You don't want to risk salmon food poisoning, and experts say you should throw it out.


When you buy fresh salmon, make sure you plan to use it within a day or two or else store it in the freezer. Salmon that has gone bad will have a fishy odor or may even smell like ammonia. If it smells this way before you've cooked it, the smell will only get worse — so throw it out.

Store Salmon in the Fridge

Never leave salmon or other perishable food out of the refrigerator for more than two hours, advises Consumer Reports. Bacteria that could cause illness can grow quickly in raw, unrefrigerated seafood, according to the Food and Drug Administration (FDA). As soon as you can, put your salmon in the fridge. If you have a long drive after you buy your salmon, bring a cooler with ice packs to keep your salmon cold.


Salmon in the fridge should be stored below 40 degrees F, so make sure your refrigerator is cold enough, the FDA reports. You should plan to eat your salmon within two days of buying it as long as it's fresh. According to Consumer Reports, freeze any raw seafood you won't use within one to two days.

Most reputable fish dealers will tell you when the fish arrived at the market; if not, there should be a sell-by date on the package, says Australian salmon producer Tassal. When you store your salmon in the refrigerator, Consumer Reports suggests that you store it in the main part of the fridge. You shouldn't store any perishables on the door because the temperature on this outer part of your fridge is more likely to fluctuate.


Read more: How Much Salmon Is Healthy to Eat Per Week?

Freezing Your Salmon

You can refrigerate your salmon in its original store packaging, but if you freeze it, you should wrap it tightly in plastic, foil or moisture-proof paper before storing it in the freezer, the FDA reports. Consumer Reports suggests that you not freeze fatty fish like salmon for more than two or three months.

The FDA reports that salmon, like any other frozen food, will last indefinitely in the freezer, but the quality will begin to deteriorate after that time. Salmon kept at zero degrees F will keep indefinitely. If you decide to freeze your salmon, according to the FDA, it's best to freeze it as soon as possible, and not wait until the salmon is near the end of its refrigerated life. Also, never refreeze thawed salmon.


Thaw frozen salmon gradually in the refrigerator, says the FDA — do not place it on your kitchen counter. If you must thaw your fish in a hurry, make sure it's sealed in a plastic bag and place it in a bowl of cold water, according to the FDA. Check the water often to see if the fish has thawed, and remove it from the water and cook. Your other option is to thaw it in the microwave on defrost, stopping it when the fish is icy but pliable.

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Other Things to Watch For

If you have followed these instructions carefully, your salmon should be safe when you're ready to cook it. But if your salmon was older than you thought, salmon food poisoning isn't something you want to face.


When you remove your salmon from the package, after either refrigerating or freezing it, it should not smell fishy or have an ammonia-like smell. You should also not have slimy salmon, according to Global Seafoods. Slime on salmon is another clue that it has gone bad.

If your salmon smells or is slimy, it may have been older than you thought when you brought it home or may have been left out of the fridge for too long. If it doesn't smell or look right when you take it out of the package, don't hesitate to throw it out, Global Seafoods says. Go with your instinct and avoid any bouts of food poisoning.

If your freezer is set above zero degrees F, ice crystals may form in your fish, and you may have mushy salmon after thawing. Even if your freezer is set at the right temperature, but you haven't properly sealed your fish before freezing it, water molecules will try to escape, causing your salmon to become freezer burned, explains the Library of Congress. Air can then get into your salmon. This salmon is safe to eat, but it probably won't taste very good.

The FDA has several additional guidelines:

  • Fish should smell fresh and mild, not fishy, sour or ammonia-like.
  • A fish's eyes should be clear and shiny.
  • Whole fish should have firm flesh and red gills with no odor. Fresh fillets should have firm flesh. The flesh should spring back when pressed.
  • Fish fillets should display no discoloration, darkening or drying around the edges.

Read more: 9 Excuses to Eat More Seafood

Preparing Your Salmon

If you've followed safe salmon storage guidelines, you will be able to enjoy your salmon when you are ready to cook and eat it. The FDA suggests cooking your salmon to an internal temperature of at least 145 degrees F. You can use a food thermometer to test the temperature. If you don't have one, however, the FDA says fish is cooked when the flesh is clear and the meat flakes easily with a fork.

By cooking it to 145 degrees F, you're reducing the chances of any food poisoning or other food-borne illness, Consumer Reports says. When serving, the FDA says to keep cooked seafood hot until you're ready to serve it. If you decide to chill your salmon, put the cooked salmon in the refrigerator until you're ready to serve it.

Follow the two-hour rule after your salmon is cooked. Never leave it out for more than two hours, or one hour if temperatures are above 90 degrees F. It's best to serve and eat salmon immediately after it's cooked or chilled. Salmon is a healthy food choice, so go ahead and savor its flavor.