Summary This procedure was evolved in order to follow tocopherol degradation in oxidizing milk fat. It combines saponification, in the presence of pyrogallol, to destroy tocoquinones and essentially all fat peroxides, chromatography on SnCl 2 + HCl-treated Floridin (Kjolhede) to remove carotenoids, possible residual peroxides, steroids, etc., and color development in benzene-ethanol with ferric chloride and bipyridyl in acetic acid solution (Devlin and Mattill). Pyrogallol was effective in preventing tocopherol destruction during saponification and was superior to saponification under nitrogen. Complete saponification was effected by using 17ml. of 3.5 N KOH per 10g. fat. If saponification was eliminated, the treated Floridin column reduced tocopheryl- p -quinones but not tocopheryl- o -quinones. The former were similarly reduced by the Quaife and Biehler hydrogenation procedure. These reduced compounds are measured as tocopherols.