AbstractThe rate of autoxidation of mixtures of triunsaturated glycerides and tridecanoin was decreased by randomization with sodium methoxide. A theory, based on the hexagonal packing of glyceride acyl chains in the molten state, was proposed which accounted for the observed efforts on the rate of autoxidation. The theory suggests that the concentration of the unsaturated fatty acids on the 2‐position of glycerol should stabilize a fat towards autoxidation. This was confirmed with experiments on natural fats.