The effect of 100, 500 and 1000 ppm of alpha-tocopherol on the oxidati
ve stability of purified olive oil kept in the dark at 40 degrees C wa
s studied. Purified olive oil was prepared by liquid column chromatogr
aphy and was practically devoid of minor constituents with possible pr
o-oxidant or antioxidant activity. alpha-Tocopherol acted as antioxida
nt at all levels of addition, although the antioxidant effect was grea
ter at 100 ppm than at higher concentrations. In the initial stage of
autoxidation a slightly pro-oxidant effect was observed. In the presen
ce of strong antioxidants naturally occurring in olive oil, such as or
tho-diphenols, alpha-tocopherol did not show any significant additiona
l antioxidant effect during the period of low peroxide accumulation.