Why is some Rainbow trout meat pink and some is white?
Post By: CBrown Posted: 2/23/2009 7:03:53 PM Points: 490
I've noticed over the years of keeping a few trout now and then from the local lakes that some meat is pink and some is white. At Barr lake the meat looks like a salmon on every trout I have kept out of there. At Chatfield I recently caught A 4 lb. trout the meat was a little pink but barely and the smaller fish were completely white. At one of the Chatfield ponds I fished at last year my friends and I had caught a few trout, all the same size about 14 to 15 inches, we went back to cook them up and it was about a 50/50 split between pink ones and white ones. Is this from diet? Different strains of fish? Or what?
CBrown, I am no expert, but what I have been told his that in the hatchery, they feed the trout "liver pellets" and that is why the meat is white. Not sure if that is true, but maybe somebody knows the real deal. I have also been told, that once the trout is introduced into the lake they forage on such things as shrimp, crayfish, baitfish, etc... and that tends to turn the meat a orange (salmon) color. We fish the stocker local lakes and most of the time in the spring all the fishes meat is white until they have been in the lake for a while and had a chance to eat the local diet. Usually, the white meat trout has that muddy taste and maybe that is the liver pellets. Actually, do they feed them liver pellets, or is it some other supplement?
idk exactly why but i have caught numerous trout that were miles into the wilderness in high mountain lakes and their meat was pink, where as the local stocker trout's meat was white, basicall the pink meat is what you want not the nasty pond trout with white meat.
I've heard the hatchery theory before but the day I caught the 4lb my friend caught a 3.5 lb his meat was extremely pink mine was barely pink. I guess one could have come out of the hatchery and one was in the lake for a while but they both looked like they had been in the lake a while because on most of the smaller fish we caught the fins had been chewed up. The bigger ones had flawless fins.
Trout food for hatcheries depends on the maker. I have not heard of liver as being the main ingredient. The pigmentation of the meat does depend on the diet of the fish. Two fish in the same lake may not feed on the same things so their flesh color may look different. Some trout farms use an artificial pigmentation in their food (astaxanthin) that causes the meat to turn pink in the trout farm. This way when they are put in the lakes or rivers they have that pink color already. Fish with the light colored pigmentation can get the pink meat by eating a diet that has the natural pigmentation in it. Fresh water shrimp have it and many lakes and rivers especially tail waters have those shrimp in them.
I cleaned several stocker trout out of West a few weeks ago. The ones that were males had white flesh, the females had pink. This may not mean that that's the difference but it's what I saw. The white flesh is also kind of mealy.
I would argue that environment plays a large role. After the stocked trout become aclimated to a non-raceway environment they develop thier muscle. That is the flesh becomes for infused with more hemoglobin (oxygen carrying complex) because the fish swims longer distances and exhibit longer bursts in swimming. Compared with swimming a few inches to pick a a morsel of fish purina. In the raceway the fish are not challenged to do so and there is no need for such development. The more myoglobin in the flesh the darker (reddish) the meat.
The level or variation in the color from white to pink depends the particular amount of time the trout has spent in a natural environment.
Next time you're at king sooper check out the salmon....farm rasied color added.
For trout, the pigment of their flesh and outward coloration is largely influenced by their diet. For example, carotenoids (color pigments) found in crustaceans such as crayfish and freshwater shrimp are largely responsible for the red, pink and orange pigments that you find when examining fish flesh. Trout that do not have access to these types of food items would typically lack this pigmentation. As an example, hatchery trout are typically more bland in coloration in comparison to their wild cousins. This is primarily due to the fact that they are fed a formulated diet that does not include the many of the food items that provide the color pigments found in nature and more readily available to a trout foraging in the wild.
Reply by: Pathway Posted: 2/24/2009 8:00:02 AM Points: 264
The color of the meat is driven by diet. Hatchery fish are fed herring meal, which doesn't contain enough extra fat to turn the meat pink. Fish that are feeding on crayfish, scuds, planktion or any other form of crustacean or arthropod will have pink meat. Fish that have an insect diet tend to be yellowish in color. Pink meat also means lots of omega 3 oils for you guys with old hearts.
Reply by: MisterRon Posted: 2/24/2009 8:56:46 AM Points: 558
The best example I can think of is the Flamingo. Taken from SeaWorld: A flamingo's pink or reddish feather, leg, and facial coloration comes from a diet high in alpha and beta carotenoid pigments, including canthaxanthin. The richest sources of carotenoids are found in the algae and various insects that make up the staples of a flamingo's diet.
Reply by: BCIII Posted: 2/24/2009 10:02:15 AM Points: 3751
This is a diet issue. Scuds and Shrimp will cause the meat to go pink. I also believe that age could also be a factor. The older the fish, the larger, the larger the fish, the more it eats meaning more food of this type be placed in the body.
Diet. Some hatcheries will feed a special food to enhance the red/pink pigment. Crustaceans, as already mentioned, influence this. However, anecdotal evidence in my observations, I have seen larger fish lose this pigment of the same species. This could be a ontogenetic shift or different prey sources as a fish grows in size.
I fished soon as the ice came off, all fish were pink (salmon colored) inside the place hadn't been stocked yet, last fall stockers were white meated. I believe their overwinter diet played abig roll in their meat color.
It is based on diet, and while a fish is a fish, coloration can be important, for example bass fisherpeople in some part of the country will look at a bass' coloration and figure out if they are feeding on crawfish or not.