Abstract: In order to evaluate the stability of crude and refined fish oil at different storage temperatures, fish oil samples were stored in four thermostats at 35, 25, 15 and 5 ℃ for 120 days, respectively and changes in physicochemical indexes (acid value, peroxide value, and anisidine value), fatty acid profile, and volatile compounds were detected at regular intervals during the storage period. The results showed that the effect of storage temperature on the quality of fish oil was significant and the higher the temperature, the worse the stability and the greater the quality changed. Moreover, the stability of refined fish oil was worse than that of crude fish oil. During the storage period, the acid value, peroxide value and anisidine value of fish oil increased significantly; the content of total saturated fatty acid (SFA) increased, and the content of total unsaturated fatty acid (UFA) decreased, thereby decreasing the overall degree of unsaturation. In addition, the volatile flavor compounds 1-penten-3-ol, nonanal, hexanal, 2-nonanone, 2-undecanone, acetic acid, and butyric acid changed significantly, greatly affecting the overall flavor of fish oil. The results from the present study will provide a theoretical basis for improving the storage stability and prolonging the shelf life of fish oil.

Key words: storage temperature, physicochemical indexes, fatty acid profile, volatile compounds