Study on the oxidative rate and prooxidant activity of free fatty acids

Oleic, linoleic and linolenic acids were autoxidized more rapidly than their corresponding methyl esters. Addition of stearic acid accelerated the rate of autoxidation of methyl linoleate and the decomposition of methyl linoleate hydroperoxides. Therefore, the higher oxidative rate of FFA’s than their methyl esters could be due to the catalytic effect of the carboxyl groups on the formation of free radicals by the decomposition of hydroperoxides. Addition of stearic acid also accelerated the oxidative rate of soybean oil. This result suggests that particular attention should be paid to the FFA content that affects the oxidative stability of oils.

[1]  F. Deckert.  Gas-liquid chromatography of coumarin anticoagulants, their trimethylsilyl ethers, acetates, trichloroacetates, and trifluoroacetates. , 1972, Journal of chromatography.

[2]  R. Kleiman,et al.  Degradation of linoleic acid hydroperoxides by a cysteine . FeCl3 catalyst as a model for similar biochemical reactions. II. Specificity in formation of fatty acid epoxides. , 1981, Biochimica et biophysica acta.

[3]  H. Gardner.  Decomposition of linoleic acid hydroperoxides. Enzymic reactions compared with nonenzymic. , 1975, Journal of agricultural and food chemistry.

[4]  P. Schieberle,et al.  Decomposition of linoleic acid hydroperoxides by radicals , 1979 .

[5]  R. England,et al.  Acid-catalyzed transformation of 13(S)-hydroperoxylinoleic acid into epoxyhydroxyoctadecenoic and trihydroxyoctadecenoic acids , 1984 .

[6]  R. Holman,et al.  The rates of oxidation of unsaturated fatty acids and esters , 1947 .

[7]  Acid catalysis of a linoleic acid hydroperoxide: formation of epoxides by an intramolecular cyclization of the hydroperoxide group , 1984 .

[8]  P. Schieberle,et al.  Decomposition of linoleic acid hydroperoxides , 1981 .

[9]  J. E. Myers,et al.  Comparative rates of oxidation of isomeric linolenic acids and their esters , 1941 .

[10]  J. Terao,et al.  Products formed by photosensitized oxidation of unsaturated fatty acid esters , 1977 .

[11]  Amitabha Ghosh,et al.  Separation of polyunsaturated fatty acid esters by argentation column chromatography on silicic acid , 1972 .

[12]  J. G. Keppler,et al.  A note on the preparation of pure oleic and linoleic acid , 1959 .

[13]  E. Frankel.  Volatile lipid oxidation products. , 1983, Progress in lipid research.

[14]  J. G. Smith,et al.  Fat oxidation. I.—Preparation of Trans‐trans methyl linoleate hydroperoxide , 1961 .