DIN CEN/TS 16233-1:2011-09

This DIN SPEC 91050-1 corresponds to CEN/TS 16233-1 and can be used foodstuffs manufacturers, food controllers and established test laboratories. It specifies a method for the determination of canthaxanthin and astaxanthin in fish flesh by high performance liquid chromatography (HPLC). The method can be applied at a range above 0,02 mg/kg. The method should not be applied to the determination of canthaxanthin in poultry tissues, egg yolks and shrimp tissues due to a possible interference of canthaxanthin with cryptoxanthin and xanthophyll esters sometimes present in these matrices. Extract fish flesh by homogenising the tissue in acetone. Filter the extract and evaporate at reduced pressure using a rotary evaporator or a flow of nitrogen at 50 °C. Dissolve the residue in a mixture of n-heptane and acetone and analyse by an isocratic normal-phase HPLC. The HPLC system described effectively separates astaxanthin and canthaxanthin and these both xanthophylls from other carotenoids found in fish flesh as, for example, β-carotene, lutein and zeaxanthin. The main geometrical isomers of astaxanthin are separated from each other and from oxidation products of astaxanthin, astacene and semi-astacene. In contrast, the isomers of canthaxanthin are not separated.