Production of lipase-catalyzed structured lipids from safflower oil with conjugated linoleic acid and oxidation studies with rosemary extracts

摘要

Structured lipid (SL-safflower) was produced by lipase-catalyzed esterification (acidolysis) from safflower oil and conjugated linoleic acid (CLA). SL-safflower was then isolated by alkaline de-acidification, and its chemical characteristics were studied. Also, the change of fatty acid composition and tocopherol content was monitored during the reaction. After 2 h reaction, 18.5 mol% CLA was incorporated into SL-safflower, which further increased to 22.5 mol% after 24 h reaction. The content of (alpha-tocopherol was gradually reduced to more than 85% after 24 h. Besides, the oxidative stabilities of SL-safflower and safflower oil were studied. SL-safflower showed higher peroxide value (POV), rho-anisidine value (AV), and 2-thiobarbituric acid reactive substances (TBARS) value than safflower oil, indicating that SL-safflower containing CLA is more susceptible to oxidation than safflower oil. Rosemary extracts with different amount (100, 200 or 300 ppm) could effectively reduce the oxidation, showing the most effective at 300 ppm.