Farmed salmon isn’t naturally pink or red

In fact, if fish farmers didn’t add it, the farmed salmon would be grey. Kept in pens, they are fed a mix of ground-up anchovies and herring, fish oil, corn gluten, food processing byproducts such as wheat and soy, and, of course, astaxanthin in additive form, either derived from crustaceans or formulated in a lab. This food coloring is the most expensive component of fish feed, accounting for 20 percent of its cost, but according to salmon farmer Don Read, who works in British Columbia, “If we didn’t do it, customers wouldn’t buy it… Consumers buy what they are comfortable with.

Source: www.treehugger.com