Alcance
ISO 20633:2015 specifies a method for the simultaneous quantitative determination of vitamin E (α-tocopherol and α-tocopheryl acetate) and vitamin A (13-cis and all-trans isomers of retinyl palmitate and retinyl acetate) present in all forms of infant and adult formulas (powders, ready-to-feed liquids and liquid concentrates).Retinol is not used for fortification purposes and therefore is not addressed in this method. The innate amount in products is insignificant.Stereoisomers of vitamin E, α-tocopherol and α-tocopheryl acetate, are not differentiated in this method.