Effect of Natural Antioxidant Extracted From Rosemary Leaves On Stability Of Soybean Oil Under Thermoxidation

Abstract

This research was carried out in the directorate of laboratories- ministry of Internal Trade and consumer protection and also the Department of Food Science - Faculty of Agriculture, Damascus University to determine antioxidant activity of ethanolic and oily extracts  of  Rosemary ( Rosmarinus officinalis). The  extracts were added  to soybean oil stored for 5 weeks in the oven at 65 °C and compared with  the  synthetic  antioxidant  (BHA). The antioxidant efficacy of ethanolic  rosemary extracts  with different concentrations (1000  and 2000 ppm) and oily extract 2%  was estimated in  accelerated oxidation  conditions  (Schaal oven test) by estimating peroxide value,  free fatty acid% (Oleic acid) and total polar compounds. The results showed that Rosmary ethanolic extract  with  2000 ppm  had the highest antioxidant effect, while  oily extract 2% had  little effect on the protection of soybean oil from degradation during storage