Oxidation Stability and Shelf Life Prediction of Refined Eucommia ulmoides Seed Oil

Taking crude Eucommia ulmoides seed oil as raw material, after refining, the effects of antioxidants and temperature on the oxidation stability of refined Eucommia ulmoides seed oil were studied by Schaal oven test according to peroxide value, acid value and fatty acid content. The shelf life model of refined Eucommia ulmoides seed oil was established and the shelf life was estimated. The results showed that the antioxidant effects of butyl hydroxyanisole (BHA), tert-butyl hydroquinone (TBHQ), vitamin E (V_E), carnosic acid (CA) and L-ascorbyl palmitate (L-AP) were in the order of TBHQ>CA>L-AP>BHA>V_E, and the optimum addition of CA, TBHQ, V_E, BHA and L-AP were 0.05%, 0.02%, 0.01%, 0.02% and 0.02%, respectively. With the increasing of storage temperature and time, the peroxide value, acid value and the oxidation rate increased, the content of saturated fatty acid and monounsaturated fatty acid increased, and the content of unsaturated fatty acid decreased; the oxidation of refined Eucommia ulmoides seed oil followed the first-order oxidation kinetic reaction, and the shelf life was predicted to be 10.70, 8.76, 7.74 and 6.89 d at 25, 40, 50 and 60 ℃ respectively. Adding antioxidants could delay the oxidation of unsaturated fatty acids, and the antioxidant effect of TBHQ was the best, the shelf life of refined Eucommia ulmoides seed oil with 0.02% TBHQ could be extended to 41.41, 19.71, 12.48 and 8.13 d. It was suggested that, the shelf life of refined Eucommia ulmoides seed oil could be effectively prolonged by adding antioxidants.