title: Reactions of oxidized lipids with protein. Part 13. Autoxidation of hexanal in presence of nonlipidic components.
abstract: Hexanal is rapidly autoxidized in mixture with nonlipidic substrates even at 25 degrees C. The formation of peroxides follows the kinetics of a first order reaction with respect to hexanal (k1 about 10(-5) min-1), and is higher in mixture with casein or lysine-impregnated cellulose than with cellulose. In mixtures containing pure hexanal, peroxides are decomposed more rapidly after second-order reaction with respect to peroxides (k2 about 10(-3) mmol X kg-1 X min-1) while only slowly by the first-order reaction (k3 about 10(-5) min-1). In presence of small amounts of hexanoic acid the rate of second-order peroxide decomposition remained unaffected while the rate of the first-order peroxide decomposition increased by 4 orders (k3 about 10(-1) min-1). The presence of peroxides was percepted in the odour by sensory analysis contrary to nonvolatile lipid hydroperoxides.
mesh_terms: D000447:Aldehydes / Q000032:analysis*; D005227:Fatty Acids / Q000032:analysis; D008055:Lipids / Q000032:analysis*; D010084:Oxidation-Reduction; D010545:Peroxides / Q000032:analysis; D011506:Proteins / Q000032:analysis*
chemical_list: D000447:Aldehydes; D005227:Fatty Acids; D008055:Lipids; D010545:Peroxides; D011506:Proteins; C010463:n-hexanal