Wild salmon feed on seaweed, fish and shrimp, and astaxanthin in their bodies gives salmon a beautiful yellow color. In addition to eat small fish shrimp, farmed salmon is also fed with protein and fish oil, which makes astaxanthin insufficient and the meat color tends to turn white.

In order to improve the sensory quality of fish, breeders often feed a feed additive canthaxanthin to farmed salmon to make its meat color natural yellow.

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There are many parasites in wild salmon, among which Anisodes is the most common, which is easy to cause abdominal pain and diarrhea, but marine parasites cannot survive in human body for a long time.

In comparison, there may be fewer parasites in farmed salmon. It is worth noting that rainbow trout cultured in fresh water is sometimes used for sashimi, but its risk is far greater than salmon.

This is because parasites in freshwater fish can survive in human body, and the most common one is liver fluke. Therefore, rainbow trout cultured in fresh water cannot be eaten raw.

Baidu Encyclopedia-Salmon