Pinker salmon isn't necessarily better: the color depends on its diet
The most colorful fillet looks the best, but the pigment that gives the pink tone only indicates what the fish has eaten, not its freshness or quality.
At the fishmonger's, the bright pink fillet immediately catches the eye, while its paler neighbor looks less appealing. At the same price, the choice is usually quick, but pinker salmon isn't necessarily better.
The color comes primarily from astaxanthin, a pigment in the carotenoid family. Wild salmon do not produce it; they obtain it by ingesting small organisms, such as krill and other crustaceans, that contain it. Over time, the pigment accumulates in their tissues, giving the flesh shades ranging from pale pink to much more intense hues.
In farmed salmon, the principle is similar, with one difference: the fish farmer prepares the feed, so astaxanthin is added to the diet to achieve that pigmentation. NOAA, the U.S. agency responsible for oceans and fisheries, notes that this pigment can be natural or synthetic, and that the fish assimilates and metabolizes it in the same way in both cases.
The amount of pigment ingested and absorbed varies, and with it the resulting color. Therefore, darker flesh primarily indicates pigmentation and does not necessarily mean the fish is fresher, tastier, or of better quality.
To distinguish between two salmon, it's best to ignore the color and observe the flesh: it should be firm, shiny, and juicy, without any dry or brownish areas. The smell should be mild, never strong or unpleasant. Finally, the label provides more useful information, such as origin, species, production method, and certifications like Label Rouge or those for sustainable fishing.
