Autoxidation rates of various esters of safflower oil and linoleic acid

Autoxidation rates of five types of safflower oil esters increased in the following order: monoacylglycerol (MG), methyl ester (ME), diacylglycerol (DG), triacylglycerol (TG) and sucrose ester (SE). The differences in autoxidation rate were confirmed by measuring autoxidation of similar esters of linoleic acid. The order of the oxidation rates corresponded to the number of acyl groups per molecule. This relationship was explainable by the idea that intramolecular free radical chain reaction between actyl groups of esters occurs more rapidly than intermolecular chain reaction. The position of acyl groups also affected the oxidation rates of esters in that 1,3‐dilinolein autoxidized more rapidly than 1,2‐dilinolein. This difference in oxidation rate may result from a closer arrangement of acyl groups in 1,3‐dilinolein than those in the 1,2‐isomer.