Effect of alpha-tocopherol, alpha-tocotrienol and Rosa mosqueta shell extract on the performance of antioxidant-stripped canola oil (Brassica sp.) at high temperature

The antioxidant effects of tocols (alpha-tocopherol and alpha-tocotrienol) and Rosa mosqueta shell extract added to antioxidant-stripped canola oil (TCO) were evaluated and compared with the non-stripped oil (CO) under the same conditions. Seven oil systems were subjected to thermal treatment at 180 degrees C for 18 h. Polar compounds formation, degradation of tocols and carotenoid pigments were studied. The addition of Rosa mosqueta shell extract gave a great stability to TCO, similar to CO, with a low polar compound formation and a high retention of alpha-tocopherol compared with other TCO samples, which suggested the protective action of the minor components present in the extract. Alpha-tocopherol showed a higher effectiveness than cx-tocotrienol at high temperature. However, an increase in the level of a-tocopherol did not improve its action. (C) 2007 Elsevier Ltd. All rights reserved.