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How To Tell If Salmon Is Bad?

How To Tell If Salmon Is Bad?

Picture this: it’s dinnertime, and you’ve found a salmon filet in your fridge, unsure of when you bought it. Maybe it has a slightly fishy smell or has a weird layer of slime, but you can just cook all that off, right?


If you’ve made this mistake (like me), then you’ve probably only made that mistake once. That’s because salmon that smells bad or has a slimy film has gone bad, and deciding to eat it can make you incredibly sick. Fortunately, as long as you educate yourself on how to identify fresh salmon, you can have your fish and eat it too.

Why Salmon?

Salmon is one of the most popular ingredients on the planet, and for good reason. Not only is it delicious, but it’s also incredibly beneficial for our health. Salmon is high in omega-3s, lean protein, and B vitamins, which are great for supporting the heart, immune system, weight loss, and more. Unfortunately, those benefits go out the window if the salmon is spoiled, and you will regret eating that spoiled salmon. This is why it’s so important to make sure that your salmon hasn’t gone bad before you decide to cook it for your next meal.

See Also: How Long Does Smoked Salmon Last?

Risks Of Eating Bad Salmon

Spoiled salmon provide the perfect breeding ground for harmful pathogens, bacteria, and mold, which can lead to illnesses like food poisoning. Spoiled salmon and other fish can also cause scombroid poisoning. Symptoms of scombroid poisoning can include:

  • Abdominal cramps
  • Nausea
  • Vomiting
  • Diarrhea
  • Fever
  • Increased heart rate
  • Flushing

Scombroid poisoning occurs when bacterial growth converts the histidine in fish into histamine. Once they form, the histamines can’t be “cooked off,” causing adverse reactions in the body when eaten. Long story short, if you suspect your salmon has gone bad, it’s best to throw it out and return to the store for a fresh specimen.

How To Tell If Salmon Is Bad

1. By Smell

Animals use their sense of smell to identify if food is edible, and humans are no exception. Our sense of smell is one of the strongest ways to see if food is viable, including salmon! For the most part, raw salmon has a weak scent that could be described as “mild” or “fresh.” On the other hand, bad salmon has a strong, offensive odor that’s immediately noticeable. If you notice that your salmon has a strong fishy or ammonia-like smell, it’s probably gone bad.

2. By Sight

A slimy, opaque coating is a tell-tale sign that salmon has gone bad. Other visual signs include a dull, pale color in the flesh or discolored eyes. Fresh, raw salmon should be a vibrant pink or orange with some white striping. If your salmon still has its head, the eyes should be clear and slightly bulging with a dark pupil in the center. Sunken eyes or opaque, discolored eyes are further signs of salmon gone bad.

3. By Touch

Raw salmon that feels mushy or falls apart during handling is definitely spoiled. Fresh salmon should be firm to the touch, with flesh that springs back when pressed with a finger. If you press into your salmon filet and the meat is soft enough to leave an impression, that salmon is spoiled. Salmon that feel slimy or sticky should also be considered spoiled and thrown out.

Store Salmon Properly

The best way to avoid eating bad salmon is to prevent it from going bad in the first place. Proper storage is the first defense against salmon spoilage. At home, fresh salmon can be stored in the refrigerator or the freezer, as long as it’s under the right conditions.

1. Refrigerating Salmon

Raw salmon should be sealed before going into the refrigerator to prevent cross-contamination and preserve freshness. In the case of pre-packaged salmon, it’s fine to keep it in its original packaging. Salmon wrapped in the paper should be rewrapped in plastic wrap or an airtight container before being placed in the fridge. Once it’s been packaged properly, salmon can stay fresh in the fridge for two days. If you don’t plan to cook your salmon for a few days or more, it’s better to place it in the freezer.

2. Freezing Salmon

The ideal way to freeze fish is by packaging it so that no air can touch it. This preserves the quality of the fish and reduces the risk of freezer burn. Because salmon is a fattier fish, the quality of the meat will decline if it’s been frozen for longer than three months. The three easiest ways to freeze fish at home are:


Vacuum-sealing is the easiest and best way to freeze fish. A vacuum-sealer is required, but the investment is well worth it for people who like to keep large amounts of fish on hand.


If you don’t have a vacuum sealer, you can wrap the fish in plastic wrap, then place the wrapped fish in a resealable bag before it goes in the freezer. While this isn’t the best way to keep the freezer burn off, it’s a great way to use common household items to freeze your salmon.


Glazing fish entails dipping the fish in water and placing it in the freezer until the water turns into a frozen crust. Repeat several more times until the ice glaze measures approximately a quarter-inch thick. Then, place the glazed fish in a resealable bag and put it in your freezer.

Thawing Salmon

Proper storage is only half the battle when it comes to keeping salmon fresh. You must also thaw it properly to keep bacteria from proliferating and the meat from turning to mush. It may be tempting to use your microwave’s defrost setting, but the uneven heat distribution in a microwave isn’t ideal for thawing fish. Placing it on your kitchen counter is also dangerous because it can encourage bacteria to grow on the surface while the inside stays cold and frozen.

There are two ways to thaw salmon safely:

1. Refrigerator

Move your salmon from the freezer and leave it to thaw in the refrigerator. In most cases, 12-24 hours is all it takes for frozen salmon to thaw in the fridge. If you plan on cooking salmon for dinner, you can transfer it from the freezer either the night before or the morning of, with plenty of time to spare.

2. Cold Water

If you don’t have time to thaw your salmon in the refrigerator, you can submerge it in cold water to help it thaw faster. The water should be slightly colder than room temperature, but not colder or the salmon will remain frozen. Change the water every 10-20 minutes until the fish is thawed. Refrain from using hot water, which can cook your salmon unevenly or cause bacteria to form on the surface.