Antioxidant activity of sodium nitrite in meat

Polar lipids were extracted from raw, nitrite-treated beef and pork by a dry column procedure. The polar-lipid fraction had substantial activity in inhibiting the oxidation of linoleic acid as determined by a β-carotene bleaching method and by conjugated diene formation. The antioxidant activity of the polar-lipid fraction was stable over several months when stored in hexane at−20 C. Residual sodium nitrite, carbon-nitroso and nitrogen-nitroso compounds or products of the addition of nitrogen oxides to olefins do not seem to account for the antioxidant activity observed.