Salmon flesh colour, (after eating prawn)

[Will__]

If, as the advert tells us, salmon are pink because they eat prawns, how can this be true since all raw prawns are grey or colourless? My prawns only turn pink when cooked. (Many packets of prawns that you buy and then cook with are actually pink already because they've been cooked already and then frozen or whatever. Raw ones from the sea are not that colour.)

Presumably the element of the prawn that goes pink when cooked also turns the salmon pink when digested but what is this chemical/process?

Many thanks.

[CheekyChops]

Salmon colouring is nothing to do with Prawns:

Salmon flesh is generally orange to red in colour, although there are some examples of white fleshed wild salmon. The natural colour of salmon results from carotenoid pigments, largely astaxanthin (E161j), in the flesh.

Wild salmon get these carotenoids from eating krill and other tiny shellfish. Because consumers have shown a reluctance to purchase white fleshed salmon, astaxanthin, and very minutely canthaxanthin (E161g), are added as artificial colourants to the feed of farmed salmon because prepared diets do not naturally contain these pigments.

[heathfield]

Closely related to the Atlantic salmon, brown trout flesh is also pink when cooked, even for those fish that have spent their lives in water where there aren't any kind of shrimp, (fresh or saltwater), or prawns.

[lafrancaise]

It's not salmons, it's flamingos. The more shell fish they eat the more pink they become. Read this for a very unusual pink animal...
http://www.wiu.edu/users/emp102/DolphinWeb/end angered_dolphin.htm