Synergistic Antioxidant Activity of Sphingoid Base with α-Tocopherol on the Oxidation of Highly Unsaturated Fatty Acids

Abstract

Fish oil is very easily oxidized, as it is rich in eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Hydroperoxides from the EPA and DHA are relatively not stable to readily decompose to low molecular compounds such as aldehydes, causing undesirable flavors from the very early stage of the oxidation. Therefore, the key point for the anti-oxidation of fish oil is to prevent the formation of low molecular compounds in the early stage of the oxidation. Although many studies have been done on the volatile compounds formed in the fish oil oxidation, little volatiles have been recognized as the major contributors to the flavor deterioration. This review discusses the rapid formation of the fishy and metallic off-flavors, focusing especially on an early stage of fish oil oxidation. This review also notes the effective way to inhibit the formation of the volatile compounds responsible for the flavor deterioration.