Also known as Chinook Salmon, wild King Salmon comes in both the traditional Red King variety as well as the much rarer (only about 1 in 20) White or Ivory King salmon. While not all agree, according to experts there is little to no measurable taste or texture difference, and no difference in nutritional content, the orange color simply comes from a genetic anomaly that allows Red Kings to process the pigments from crustaceans in their diet differently.

Per Tammy Davis at Alaska Department of Fish & Game:

The meat of a typical king salmon may range from reddish-orange to pinkish-red. These kings have the genetically-determined ability to metabolize pigments in their diet, which are stored in the muscle tissue – the meat. All salmon eat small marine crustaceans (shrimp, krill and crabs) that are rich in astaxanthin, a carotenoid that is found in most sea life. Carotenoids are natural pigments, such as beta-carotene that makes carrots orange, lycopene that provides tomatoes with red color, and astaxanthin, which gives lobsters’ their red shell. White king salmon do not have the ability to metabolize these pigments from their food sources, leaving their flesh white. The ability of salmon to metabolize and store the red-orange pigment carotene in its muscle cells is determined by their genetic make-up.