The chemical estimation of vitamin‐E activity in cereal products. III.—the application of partition chromatography to the isolation of ε‐tocopherol from bran and to the determination of the individual tocopherols of cereals

Reversed‐phase partition chromatography, using a liquid paraffin‐aqueous ethanol system supported on kieselguhr made hydrophobic with dimethyldichlorosilane, has been applied to the isolation of ε‐tocopherol (5‐methyltocol) from bran. The development of the method as an alternative to paper chromatography for the determination of the individual tocopherols in cereal products is discussed. Details are given of the absorption spectra of ε‐tocopherol and nitroso‐ε‐tocopherol.