19.6.11

Stability of fish oil - Effects of temperature and light


Ph.D. Chingmin E. Tsai2, a, Joseph T. Wootena and Ph.D. David A. Otto
Department of Research The Baptist Medical Centers Birmingham, Alabama 35211 USA
Accepted 1 March 1989. 
Available online 2 June 2006.

Abstract

The extent of oxidation of fish oil with added antioxidants in a purified diet was studied after storage under nitrogen at 1°C or −16°C, and after exposure to air at room temperature with direct or indirect light. The thiobarbituric acid values showed that the fish oil diet was stable for at least two weeks when stored in the dark at 1°C or −16°C. The fish oil diet was rapidly oxidized at room temperature when the diet was directly exposed to overhead fluorescent light. However, if the diet was exposed to only indirect light it was stable at room temperature for at least 8 days.
These data emphasize the importance of light exposure when considering the stability of fish oil containing diets even in the presence of antioxidants.
The data demonstrate that when feeding animals, daily mixing and replacement of fish oil containing diets (with added antioxidants) is not necessary if the diet is shielded from direct light.
Key Words: Fish oil; Purified diet; Autoxidation; Antioxidants; Thiobarbituric acid value
1This research was supported by the National Institutes of Health Grant No. 1 RO1 HL39246 from the National Heart, Lung, and Blood Institute.