Salmon is one of the most popular and nutritious types of fish. It’s loaded with healthy fats, protein, vitamins and minerals. However, you may have noticed that salmon fillets sometimes change color from the typical reddish-pink hue to a brown or gray color.
This color change can happen for a few different reasons. It may make you wonder if brown salmon is still safe to eat or if it has gone bad. This article covers everything you need to know about salmon turning brown.
What Causes Salmon to Turn Brown?
Here are the three main reasons why salmon turns brown:
Oxidation
Exposure to oxygen is one of the most common reasons for the color change. Oxygen interacts with the fat molecules in salmon, which causes oxidation.
This process breaks down the carotenoid pigments, such as astaxanthin, that give salmon its characteristic pink hue. As these pigments fade, the flesh transitions to a more dull and brownish color.
Sliced fillets are especially prone to oxidation. The greater surface area exposed to air accelerates the reaction. Proper storage helps prevent excessive oxidation.
Drying Out
Salmon that’s left out too long may start to dry out on the surface. This causes the area of flesh exposed to air to appear brown or gray.
It’s especially common around the thinner edges and tail end of a fillet. While drying doesn’t necessarily mean the fish has spoiled, it does indicate that the quality has degraded.
Bacterial Growth
Improper handling and storage could allow bacteria to grow on salmon. As the bacteria multiply, enzymes are released that break down fish proteins into byproducts that cause off colors and odors.
Significant bacterial growth results in obvious visual cues that the salmon has gone bad, like slimy texture and foul smell.
Is Brown Salmon Safe to Eat?
The safety of brown salmon depends on a few factors:
- If it’s only a subtle surface discoloration from minor oxidation or drying, the salmon is still fine to eat.
- If the color change is accompanied by an off smell, slimy texture or other signs of spoilage, the salmon should be discarded.
- If the brown color permeates deeper through the flesh, it likely means the salmon is past its prime freshness — especially if the texture also seems mushier. It’s best to avoid consuming at this point.
Here’s a simple technique you can use to gauge the extent of the color change:
- Check the thickness of the brown area. If it’s superficial, it’s likely just surface drying.
- Poke the brown spot with your finger and inspect the underside. If it’s brown underneath, it’s a deeper oxidation issue.
- Smell the salmon. Rancid or “off” odors mean it’s no longer fresh.
As long as the brown color is surface level without any foul odors, the salmon is likely still safe to eat. You may just need to remove the discolored outer layer.
How to Prevent Salmon From Turning Brown
Proper handling and storage helps slow the oxidation process and prevent salmon from turning brown too quickly:
- Keep salmon as cold as possible. Store fresh fish on ice or in the coldest part of the refrigerator.
- Don’t expose salmon to direct sunlight, which accelerates oxidation.
- Wrap fillets tightly in plastic wrap or parchment paper to limit oxygen exposure.
- Cook salmon soon after purchasing for maximum freshness and color retention.
- Cut away any brown areas on the surface before cooking.
- Add an acidic ingredient like lemon juice or vinegar to help preserve color.
- Don’t overcook salmon. Higher temperatures increase the rate of oxidation.
What Does Brown Salmon Taste Like?
If the brown color is only superficial, it doesn’t affect the flavor at all. The fish underneath still tastes like fresh salmon.
However, if the brown color extends deeper into the flesh, the texture and moisture content start to degrade. At this point, the salmon tastes drier and the flavor is diminished.
Any rancid or “off” odors mean the salmon has spoiled and will not taste good. Always rely on your senses of smell, sight and touch — not just taste — to determine if salmon is still fresh.
Is Brown Salmon Safe to Cook And Eat?
Brown salmon is safe to cook and eat as long as:
- The brown area is surface level only.
- There are no sour, rancid or “off” odors.
- The flesh still appears moist, shiny and firm.
If the brown areas are limited to just the surface, simply trim them off along with the skin. The remaining pink flesh is still fine to cook as long as it’s been stored properly.
However, if the brown color penetrates deeper into the salmon, cooking and eating it poses some risks:
- Bacterial growth may have caused the color change and could lead to foodborne illness.
- The drier, mushier texture makes the fish less palatable.
- Off flavors become more concentrated during cooking.
- Harmful oxidized lipids may have formed.
For optimal safety and eating quality, it’s best to discard brown salmon if the discoloration extends beyond the very surface.
Can You Freeze Brown Salmon?
It’s not recommended to freeze salmon once it has turned brown:
- Freezing can’t reverse the oxidation process — it will remain brown when thawed.
- The texture and moisture content will degrade further.
- The surface may become drier and flakier when frozen.
- Bacteria can continue to grow even at frozen temperatures.
For the highest quality, freeze salmon soon after purchasing before any color changes happen. Portion into airtight bags or containers before freezing.
If brown areas are very minimal, you may be able to get away with trimming them off before freezing. But it’s generally safer to freeze salmon when it’s still fresh and pink.
Can You Smoke Brown Salmon?
You can technically hot or cold smoke salmon that has turned brown, but the results may be undesirable:
- The brown areas will likely become tougher and drier when smoked.
- The flavor will be more dull compared to fresh salmon.
- Smoking can’t cover up rancid flavors if bacteria have grown.
For best results, hot or cold smoke salmon as soon as possible after purchasing. Only smoke fresh salmon with no signs of spoilage.
If brown spots are very minimal, trim them off along with the skin before smoking. Avoid smoking if the brown color penetrates deeper through the flesh.
The Best Way to Use Brown Salmon
If your salmon fillet shows some slight discoloration, trimming off the brown layer is the best option. Use only the fresh pink salmon underneath.
Some good ways to use up trimmed brown salmon pieces include:
- Make salmon patties, croquettes or fish cakes.
- Use in seafood stews, chowders or mixed rice dishes.
- Add to salmon salad or pasta salad recipes.
- Make homemade salmon pet food.
Mincing the browned bits helps distribute any oxidized parts evenly so they’re less noticeable.
However, throw away heavily oxidized salmon with extensive brown discoloration that penetrates deeper than the surface. The degraded texture and moisture make it unsuitable for consumption.
Frequently Asked Questions
Why did my salmon turn brown after cooking?
Higher temperatures cause salmon to oxidize and turn brown more quickly. Overcooking leads to a more dull, brownish color. For best color retention, avoid overcooking salmon past the point of opaque pink flesh.
Can browned salmon make you sick?
Brown salmon is unlikely to make you sick if the discoloration is superficial and there are no off odors or slimy texture. However, if bacteria have started growing, causing deeper color changes, consuming the salmon could lead to food poisoning.
How can you tell if brown salmon is spoiled?
Signs that brown salmon has spoiled and should be discarded include:
- Pink flesh under the skin has turned brown
- Strong, sour or rancid odors
- Slimy texture
- Dull, mushy flesh
If the brown areas are only on the very surface and the flesh appears moist and firm with no smell, it is likely still fresh.
Should I avoid eating the brown parts of salmon?
It’s best to remove and discard any brown areas on salmon fillets, especially if the discoloration extends deeper than just the surface. While not necessarily unsafe, the brown flesh loses moisture and texture quality during cooking.
Is it OK to eat brown salmon raw?
It’s not recommended to eat any raw salmon that has turned brown. The brown color means oxidation has occurred and bacteria may be present. Only consume raw salmon when it is very fresh and still has the characteristic translucent reddish-pink color.
The Bottom Line
A brownish color on salmon doesn’t necessarily mean it has gone bad. Surface discoloration is common due to oxidation and drying out. As long as the brown areas are minimal and the flesh still looks and smells fresh, the salmon is likely still safe to eat.
However, deep brown color extending through the flesh indicates the quality has diminished. At this point, it’s best to discard the salmon. For optimal safety and quality, use salmon as soon as possible after purchasing.