Condensed astaxanthin of pigmented oil from crayfish carapace and its feeding experiment.

The pigments were extracted from crayfish carapace with soy oil. Astaxanthin and its esters were purified and concentrated by using microcrystalline cellulose adsorptive chromatography. The concentration of the purified pigments was approximately forty times that of the original pigmented oil. The separation of the pigments from the pigmented soy oil enabled us to reduce the amount of oil necessary to fortify the diet. In a feeding trial, rainbow trout Salmo gairdneri were fed with the diets containing the purified pigments and desirable pink coloration was found in the flesh. The analysis of the pigment in the test diets and flesh of rainbow trout was carried out. The diets with the higher levels of oil had a higher level of pigment decomposition.