AbstractSilicones (polydimethyl siloxanes) greatly increase the oxidative stability of an edible oil at high temperature. The effect is demonstrated here, using a thin layer chromatography technique to follow the oxidation of the oil. The minimum fully effective concentration corresponds to a monolayer of silicone on the air‐to‐oil surface. Using an atomic absorption technique, estimates have been made of the amount of silicone picked up on food fried in a silicone‐containing oil. When potato chips are fried in an oil containing 2 ppm silicone or more, the silicone content of the used oil is reduced to below 1 ppm and the surplus is taken up by the potato chips. In view of this pickup effect, and because only a very small amount of silicone is required to protect the oil, it is not desirable to use the silicone at levels higher than 2 ppm. Silicones should therefore be added in a controlled manner by the frying oil manufacturer.