Oxidation kinetics of sardine oil have been determined at 40, 65 and 90 °C by measuring concentration of primary and secondary oxidation products in the presence of commercial immobilized lipases (Lipozyme 435, Lipozyme RM and Lipozyme TL) commonly used as biocatalyst in lipid modification reactions. Oxidation products concentration was found to be lower when the immobilized lipases were added at the highest temperatures studied. The lowest oxidation indices were observed in the presence of Lipozyme RM.
Although the mechanism to explain this decrease in the oxidation products is not still clear, these results might indicate that the use of these immobilized lipases in lipase-catalyzed reactions of fish oils at high temperature (90 °C) will yield higher reaction rates and also a reduction of the oxidation products formed due to oxidation of polyunsatured fatty acids
