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Ever Wondered: Why is wild salmon a deeper red than farmed salmon?

When it comes to salmon, color is king.

September 11, 2013
Whole wild-caught salmon at the New Fulton Fish Market [Image credit: Andrew P. Han].

It’s 1:30 AM at the New Fulton Fish Market in the Bronx, New York City. As forklifts zip pallets of seafood through ice-packed loading bays, the fishmongers of Lockwood & Winant are selling fresh Pacific King salmon right off the plane from Washington. Further down the large, cold, cavern, Montauk Seafood Co. has Coho salmon straight in from Alaska. These wild-caught fish glow a deep pink, fleshy ingots glistening on ice. Later today, they’ll be carved into sushi gemstones, gingerly set upon rice and seaweed settings at five-star restaurants in Manhattan.

Farm-raised Atlantic salmon is also for sale here, like the fillets and steaks at your average grocery store. Based on price alone, the farm-raised fish is a steal — $3 per pound wholesale versus $10.50 per pound for wild caught. But a side-by-side comparison reveals a distinct difference in color: farmed salmon is light pink — almost orange — and has a flatter shine, without the rich hues of red.

Color may not be the biggest difference. Nick Stockton — friend and fellow science writer, who once worked on an Alaskan salmon boat — says he tries to only eat wild salmon, mostly “to support the fisheries,” but also because it has superior taste and nutritional content. Yet color is such an important indication of quality that farmers will even dye the farm-raised fish red to increase its appeal.

So why is wild salmon a deeper red than farmed salmon?

Unlike beef, which acquires its distinct red hue from contact with oxygen in the air, salmon meat gains its color through the fish’s diet. Out in the ocean, salmon eat lots of small free-floating crustaceans, such as tiny shrimp. These crustaceans are filled with molecules called carotenoids, which show up as pigments all over the tree of life. In fact, if you’ve ever known a kid who turned orange from eating too many carrots, you’ve seen carotenoids in action. It’s these carotenoids that account for the reddish color of the salmon, as well as the pink color of flamingoes and the red of a boiled lobster.

Farmed salmon, however, aren’t fed crustaceans. Instead, they eat dry pellets that look like dog food. According to the Atlantic Canada Fish Farmers Association, salmon chow includes ingredients such as “soybean meal, corn gluten meal, canola meal, wheat gluten and poultry by-products.” Carotenoids, which are also essential for regular growth, can also be added to help give the fish its distinctive color.

Clearly, color counts. But as Tammy Davis notes on the Alaska Fish and Wildlife News blog, color isn’t the only thing that makes for a tasty fish:

Some king salmon – about one in 20 – have white meat due to an inability to process these pigments in their food […] In past years white king sold for about sixty cents less per pound than the more familiar red-fleshed king, and some fish buyers enjoyed this rarer king salmon for a bargain. Nowadays many believe white king’s flavor is more delectable than their more common cousin. The marketing tide has turned and now the fairer fish, marketed as “ivory king,” brings a higher price.

So, in your salmon eating future, judge a fish not by its color, but by how well it goes with lemon, butter, and capers or soy sauce and wasabi.

About the Author

Andrew P. Han

Andy Han studied astronomy and the history of science at Dartmouth College, but his main interests have expanded to include evolutionary biology and genetics as well. Having preferred non-fiction to fiction since the age of six, he is on a mission to find out as much as he can about the Universe. An avid athlete and eater, he’s excited for all New York has to offer, especially SHERP.

Discussion

16 Comments

Jim AmcIntosh says:

Nice attempt at a product attack, which you’re not even very good at. Terribly written piece. The point is: wild or farmed is good for you. To compare tastes, one has to discuss species, not whether farmed or wild. 6 different salmon Species taste different and all have a slightly different color based in their diet. Your fishermen buddy is at least honest-supporting the friends he has by buying their salmon. You however?

Pam Dawkins says:

Salmon – farmed or wild or wild-caught or ranched – all receive their colour from eating nutrients in their field. All good for us to eat – real good.

The rest of your blah, blah, blah, is just trying to attack the (perceived) competition to bolster your love for “wild” salmon. It’s not too subtle bud.

In fact, your confusing little story will only turn consumers away and to the hot dogs instead. Nicely done.

The colour difference between farmed and wild salmon isn’t just because of what they eat. It is also because they are different species.

Like sockeye and pink salmon have different colours because they are different species, Atlantic salmon (farmed) also have a different colour from sockeye and king salmon because they are different species.

The flesh colour of a wild-caught Atlantic salmon would look the same as the flesh colour of a farmed Atlantic salmon.

Your sentence about farmed salmon being “dyed,” citing a 10-year-old newspaper opinion column as a source, is untrue and should be removed from this article. Farmed salmon is not dyed, never has been and never will be. Like you point out, all fish get their colour from what they eat.

JAMES FENDERSON says:

Every Alaskan knows winter white kings are the best. The Stikene River run is 20% White Kings. Tasty doobie!

Capo says:

Of course salmon farmers are going to lie about it…they count on the public NOT to do their homework!

The deceptive pink/red/orange color found in farmed salmon is nothing more than a synthetic color chemical known as “Carophyll” that is designed to look like astaxanthin and other natural salmon colorings. Hoffman-La Roche and others actually have a salmon color chart known as “SalmoFan” that allows salmon farmers to pick the shade of pink they want added to their salmon food, much in the same way that one would pick a wall paint color using color tiles at the hardware store.

Learn more: http://www.naturalnews.com/037136_food_industry_salmon_artificial_colors.html##ixzz2huYH3Lr7

https://www.google.com/search?q=salmofan+color+chart&espv=210&es_sm=122&tbm=isch&tbo=u&source=univ&sa=X&ei=qdxeUqmFLYb5iQKkwYGYCw&ved=0CDQQsAQ&biw=1280&bih=613#facrc=_&imgrc=cVuRwZM2ei4IgM%3A%3B6rwTRpyWcl8WMM%3Bhttp%253A%252F%252Fwww.edwardtufte.com%252Fbboard%252Fimages%252F0000c7-698.jpg%3Bhttp%253A%252F%252Fwww.edwardtufte.com%252Fbboard%252Fq-and-a-fetch-msg%253Fmsg_id%253D0000XT%3B700%3B474

It is my understanding that salmon farming is not good for the environment and in general is not nearly as healthy to eat as wild salmon. The salmon farms are in the ocean off the coast of Chile and in some of the rivers in Canada. They are contained to the point where in general they live in their own excretions, does not sound healthy to me. One of the Salmons primary foes if you would are the sea lice. When the wild salmon come up the river some are affected by the sea lice but in time the river naturally filters this out. In some of the farms the sea lice are rampant due to the fact that filtering is not as effective other than in self-contained farms with the latest equipment. The problem with the sea lice on the rivers has actually affected the wild salmon. It is my understanding that on the farms chemicals are used to rid the water of the sea lice, the chemicals can’t be good for the fish. Maybe not in all cases but it is my understanding that dye is used for the farm raised salmon to give them their color. The standards for Farm raised salmon are also not as strict as the wild salmon. This information is from different articles that I read and because of this I choose to eat the wild salmon.

Also depends on which type of salmon. Sokeye are really bright but Pink salmon are, well, pink. I understand the need for farmed salmon.

Helen perry says:

I am so confused. I wish we could get the real truth. But where do we go for that. I’m inclined to believe that wild caught Alaskan is the best but how do I really know that. I know it’s a lot more expensive

me says:

Um, there is no such thing as wild-caught Atlantic salmon. All wild-caught is Pacific only. Atlantic salmon is farm-raised only.

Miles Mitchell says:

Interesting the first few comments must be by farmed salmon company shrills. Eat farmed salmon, it is good for you!!! Not likely. Sure, if I put a lot of food coloring into everything I eat I could turn blue. My color would be from what I ate. The question not raised or answered? Is it good for a farmed salmon to be eating the left overs from soy bean oil, corn oil or canola oil production? After manufacturers squeeze soy, corn or canola seeds they have a mash left over. They process the remaining garbage into pills and feed it to livestock. Mmmm, nutritious. I am sorry, but if you eat garbage you are garbage and so is farmed fish. Let’s not forget that farmed Atlantic salmon has been tinkered with on a genetic level and no one really knows what that does. From Wikipedia: https://en.wikipedia.org/wiki/AquAdvantage_salmon

They genetically modify the fish to grow year round vs seasonally. Children have growth spurts. There could be serious developmental issues if they were forced to grow all of the time.

BJ says:

Where did you get the idea there is no such thing as Wild Atlantic Salmon? I have caught many wild Atlantic Salmon. They swim up our rivers in the UK every year!

Karl Parkes says:

Here in Australia,we have many salmon farms down in Tasmania,which is the most southern state and therefore,the water is colder.The farms stock the Atlantic salmon variety and they [the farmers] admit to feeding colouring agents to their fish in the feed diets to obtain a pink/red hue.As for the feed menu,it is basically dog pellets and the “poultry products” are ground up beaks,feet and legs so nothing goes to waste.The big problem here in Oz is that the retailers try and sell the farmed “pink/red” salmon at the same price as the properly wild caught sockeye..and there is a definite difference.

JAMES BOYER says:

I SPENT FIVE YEARS IN THE SEAFOOD CATCHING AND PROCESSING BUSINESS AS A NATIONAL SALES AND MARKETING EXECUTIVE. I AM ALSO A HEART PATIENT AND I CAN SOLVE THE DEBATE EASILY, EAT WILD CAUGHT ONLY!!!! THE LAST TIME I DID RESEARCH IN THE SALMON FARMING INDUSTRY IN SOUTH AMERICA, THE LACK OF ADEQUATE SANITATION WAS APPALLING, I DON’T SWIM IN MY TOILET BOWEL, DO YOU? WALLY WORLDS INFLUENCE AND BUYING POWER HAS FORCED THEM TO CLEAN UP THEIR ACT IS THE SCUTTLEBUTT, HOWEVER MY CARDIOLOGIST WHEN ASKED IF ABOUT WILD CAUGHT VERSUS FARM RAISED ASKS THE QUESTION, DO YOU HAVE A DEATH WISH? WHICH IS AN EXAGGERATION, OR IS IT? JAMES BOYER

wolfgang says:

what about the much touted quality of the faroe island salmon

Aspen says:

So where do we buy wild caught White King Salmon, and how high is the mercury level in it! I’ve stopped eating albacore tuna and salmon due to mercury levels (never eat farm raised fish I strongly agree, same with farm-raised shrimp) Now I’m concerned about the Krill oil I’m taking, I read about krill and possible levels of mercury being on the lower side also have been researching krill oil company processing, it sure doesn’t’ sound too promising, any feedback?

Melissa Ball says:

Just a brief comment because I actually just went to the grocery store to purchase salmon. The clerk told me that the salmon was color added. On a wonderful adventure a couple years back, my son and I visited the Bonneville Dam in Oregon where an Oregon Fish and Wildlife person walked us through the entire place, we had a tour of the dam, a very detailed explanation of the dam, the electricity it produces and the storage of that electricity.. blah blah… and the fish hatchery. It is huge. There are tons of them all over Oregon with amazing Oregon Department of Fish & Wildlife people to provide so much amazing information!! Super EDU!!
Schools will actually take trips there. This is normal…(I think my oldest went when he was little and I was a parent chaperone) Anyway… I asked the question to the person who had the skillset and education to provide me the correct answer.. she said no, they do not feed the fish any kind of dye or supplement that dyes the fish meat. It is made of soybean and other supplements, but I can’t recall everything she said….but 100% she did say they do not feed the fish dye. You can purchase little cups of food yourself for 25 cents (its a beige color)and also feed them.. You can find out the answer you seek by contacting your local, or any, Fish and Wildlife Department. At least, that’s how they do it in Oregon so if all else fails, call Oregon. They will be more than happy to provide you the information you seek. :)

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