Abstract:Mackerel has high histidine content, thereby suffering from quality deterioration during frozen storage and consequently affecting its safety for human consumption. To investigate the oxidation characteristics of lipids during its frozen storage, mackerel were frozen at ?18 ℃ and evaluated for flavor, acid value (AV), peroxide value (POV), thiobarbituric acid reactive substances (TBARs) value and fatty acid composition (FAC) after 0, 10, 20, 40, 60, 80 and 100 days. The results showed that nitrogen oxides were the main flavor substances in mackerel at the early stage of frozen storage. The intensity of volatile flavor substances was gradually enhanced with increasing freezing time. Both the AV and POV rose, then decreased and finally increased again. The TBARs value showed a significant upward trend; the longer the storage period, the higher the growth rate. FAC analysis demonstrated that the content of saturated fatty acids increased with prolonging frozen storage time, while the content of unsaturated fatty acids showed a decreasing trend; the degree of lipid oxidation increased.