What determines the color of Trout Meat?

[MikeFishes]

Is it only age? Or is it the species or habitat? Maybe it's the Diet?

[Derrick-k]

It depends mostly on what they have been eating. Or how recently they were planted, cutthroat in general have darker meat, because there diet consists mostly of smaller fish. Rainbow, depending on how big they are eat mostly bugs. In general the small 8in or smaller fish will have white meat because their diet consists mostly of bugs, and the big 14in+ fish will be nice pink meat.

[Marc Martyn]

I think that it has to do with the environment it lives in and diet. This has been an ongoing question for as long as I can remember. I have heard all kinds of theories and honestly I don't know. Fire off an email to WDFW and ask one of the fish biologists and then post his/her reply.

[crappie007]

What about the orange color meat on a brown trout.
Orange because of their diet? anyone got a theory on that one?

[MikeFishes]

What about the orange color meat on a brown trout.
Orange because of their diet? anyone got a theory on that one?

The reason I ask is cause I cooked up some trout that I've caught tonight. I had a couple of smaller ones that were white, but the rainbow that I caught out of Lk Wa on Saturday was nice and orange (and much better tasting). Although, the smaller ones had a nice mellow flavor.

I'll do what Marc suggests and post up a reply.

[crappie007]

I've always wondered myself why trout had differnt color
meat, so I was glad to see you asked, the brown trout I catch
at Rock lake have orange color meat and it always struck me
as a weird thing. I dont remember if they tasted better, although
my father-in-law will tell you in a second he thinks the orange
meat is always better.

[Marc Martyn]

What about the orange color meat on a brown trout.
Orange because of their diet? anyone got a theory on that one?

I believe that the diet plays an big part is color, both in the meat and skin color intensity. Much like a person that is deficient in protein, there hair does not have the sheen that a person on a good diet does.

The reply from the game department should be very educational.

[iPodrodder]

Size and age is the most important thing. Diet is the second biggest thing, and hatchery trout tend to have whiter meat than their native friends relative to size and age, because they've been hand fed pellets their whole life. But they start to change the longer they've been in a lake.

[Fish Antics]

Actually . . . the biochemistry is well documented. The carotenoid pigments, more commonly referred to as carotene pigments, in insects and crustaceans aren't metabolized in "salmonids" as they are in other types of fish. The pigments build up and color the tissue, much like the red/pink coloration in flamingoes.
The same pigments are found in carrots and fall deciduous tree leaves. They are common.

In the old days frozen blocks of krill (shrimp with high concentrations of red/orange carotene pigments) were fed to the trout at the hatchery, a few weeks prior to release, to turn the tissue pink to satisfy anglers.

The red color associated with sockeye salmon is perhaps the greatest example. Pink salmon (humpies) are pink in color and sockeye are red because the humpies only live for 2 years compared the the sockeye that traditionally are 4 year cycle fish - so sockeye have more time to consume krill (and accumulate the carotene pigments in their tissue) hence:darker red coloration.

The krill can be so abundant in the ocean off of the Alaskan coast that their sheer numbers can turn the ocean as red as tomato soup - plenty of food for schools of feeding salmon. Sockeye brains have evolved to specifically target on krill populations by detecting the "odor"of krill. THose who can find the food survive. And, by the way - the great baleen whales also strain the krill from the water. Because mammalian physiology is different there is no accumulation of the carotene pigments as there wouldn't be in you are me regardless of how much we consumed.

Krill are marine crustaceans. So what about the trout in fresh water you ask? The invertebrate life in ponds and stream also have carotene pigments . .the more the fish eat the more pink the tissue.

It is interesting to note that some outward migrating juvenile chinook salmon (kings) swim southward from the Columbia River, Fraser River, and as they leave Puget Sound to migrate off the coast of California. While there are plenty of euphausiid shrimp (krill) in the great Alaskan gyral, not so south of Washington. So south- migrating kings eat herring, sardines, and anchovy. When they return to their homestreams without having intercepted krill, their tissue does not have the pigment - those are the ones we call "white Kings"

A shorter answer would have been "cause they eat bugs!"

I can give more specifics about the biochemistry pathway if there is interest. You are on your own about the taste!

[Marc Martyn]

Great Post! There is a big interest. This information that you are furnishing us is too valuable to be lost in a forum thread. May we ask you to write an article for the site and post it in one of the writers columns? Contact Mike Carey about how to go about it and he will guide you in the right direction.
Information like this is very informative. Thanks for posting!

[Fish Antics]

Thanks Marc . . i was afraid of answering with "more than anyone wanted to know" . . but these fish are so fascinating aren't they? I would be glad to post a more detailed description . . it's nice to be able to look at a salmon egg and be able to tell your kids or grandkids why the egg is red (the carotene pigments passed on from the female).

Good fishing!

[Marc Martyn]

That's what this site is all about...... learning. Thanks for you input. Looking forward to your articleo:)

[MikeFishes]

I agree with Marc! This is great information and would be a great addition to the articles of the site! Thanks for clearing that up.

[crappie007]

I agree with Marc as well' awesome post...
No more wondering and I can share this information
with my father-in-law and anyone else who asks me
during my travels.

[Anglinarcher]

Micropterus - well done.

And to answer some of the other questions, yes the Browns in Rock are orange fleshed. The color depends to some extent on what carotenoid pigments are left after eating, and what food source the fish is eating. The browns in Rock eat a lot of crawfish, which we all know are full of carotenoid pigments (try boiling one and see for yourself).

For example, I once fished a lake that had Lakers planted in it. The flesh was orange, although a lighter color than the Rock Lake Browns. They were keying in on fish that ate scuds (high in caratenoid pigments). You are what you eat, so in this case, they were what their food was eating (HEHE).