What Exactly Is the Brown Part of Salmon?
The brown or gray-colored strip of flesh you see between the skin and the pink meat of a salmon fillet is a type of muscle tissue known as the 'bloodline' or dark muscle. This slow-twitch muscle is used by the fish for continuous, sustained swimming, as opposed to the fast-twitch white muscle used for quick bursts of speed. It gets its darker color from a higher concentration of myoglobin, a protein that stores oxygen, and contains a denser network of blood vessels.
The Nutritional Power of Dark Muscle
Due to its function and composition, the brown part of salmon is actually more nutritionally dense than the surrounding pink flesh. While many are tempted to scrape it off, doing so removes a potent source of beneficial compounds.
Here are some of the key nutritional benefits:
- Higher Omega-3 Fatty Acids: The fat in salmon is where the beneficial omega-3 fatty acids (EPA and DHA) are stored, and the brown muscle layer has a higher fat concentration. These fatty acids are crucial for heart health, brain function, and reducing inflammation.
- Rich in Vitamins and Minerals: This area also contains a higher concentration of important micronutrients, including iron, zinc, and various B vitamins.
- Excellent Source of Protein: Just like the rest of the fillet, the dark muscle is a great source of high-quality protein necessary for muscle repair and overall bodily function.
Brown vs. Pink Salmon Meat: A Comparison
To help you decide if you want to include the dark muscle in your meal, here is a breakdown of the key differences between the two types of salmon flesh.
| Feature | Brown/Dark Muscle | Pink/White Muscle |
|---|---|---|
| Flavor | Stronger, more intense, and often described as 'fishier' due to higher fat content. | Milder, more delicate, and less pronounced in flavor. |
| Texture | Firmer and more dense, with a higher fat content that can make it slightly oilier. | Softer, flakier, and more typical of what people expect from salmon fillets. |
| Nutritional Density | Higher in omega-3s, iron, and zinc. | Still very nutritious but contains slightly less fat and specific minerals. |
| Freshness Indicator | The color can indicate freshness; a light red hue is freshest, while a dark brown or green color can signal older or spoiled fish. | Remains a consistent pink color, making it a less reliable visual indicator of age. |
How to Handle and Cook the Dark Meat
While the brown part is perfectly safe to consume, its stronger flavor and texture mean it might require a different approach than the pink flesh. Most culinary experts agree it is a matter of personal preference, but here are some tips:
- Freshness Check: Always prioritize fresh fish. As with any food, if it has a strong ammonia-like smell or feels slimy, discard it. A light, reddish bloodline is a good sign of freshness.
- Incorporate into Recipes: If the flavor is too intense on its own, try flaking the cooked dark meat into a salmon salad or mixing it into a fish cake. The stronger flavor can add depth to these dishes.
- Crisp the Skin: If you are pan-searing or grilling, keeping the skin on and crisping it up can help render the fat in the brown layer, improving its texture and integrating the flavor more subtly.
- Scrape It Off (Carefully): If you are making a delicate dish like sashimi and want a purer flavor, you can scrape off the dark meat with the back of a knife after removing the skin. However, be aware that you are discarding some of the most nutrient-rich parts of the fish.
Potential Considerations: Farmed vs. Wild Salmon
When it comes to the fatty brown part, the source of your salmon can be a factor. Concerns about contaminants like PCBs gathering in the fatty tissues have been raised, particularly for farmed salmon, depending on their feed and source. Wild-caught salmon is generally considered to have lower levels of these pollutants. The UC Berkeley Wellness Letter advises that while farmed salmon is fine to eat, it should not be your sole source of fish. If you are concerned, opting for wild salmon or sourcing from a reputable provider is a wise choice. It is also important to note that the omega-3 content can vary between wild and farmed salmon, though both are excellent sources. For more detailed information on salmon's overall nutritional value, you can refer to authoritative sources like Healthline's detailed guide on salmon nutrition.
Conclusion: The Final Verdict on the Brown Part
The brown or gray part of salmon is not only edible but also a valuable nutritional component of the fish. It is safe to consume and is packed with heart-healthy omega-3s, vitamins, and minerals. While its stronger, oilier flavor may not appeal to everyone, its health benefits are undeniable. For the best experience, always choose fresh, high-quality salmon, and decide whether to eat the dark meat based on your personal taste preference and the dish you are preparing. By understanding what this dark muscle is, you can make an informed choice and avoid wasting a perfectly healthy part of your meal.
