Structured lipids from high-laurate canola oil and long-chain omega-3 fatty acids

The lipase-assisted acidolysis of high-laurate canola oil (HLCO; Laurical 25) with long-chain n-3 FA (DHA and EPA) was studied. Response surface methodology was used to obtain a maximal incorporation of DHA or EPA into HLCO. The studied process variables were the amount of enzyme (2-6%), reaction temperature (35-55 degrees C), and incubation time (12-36 h). The amount of water added and the mole ratio of substrates (oil to DHA or EPA) were kept at 2% and 1:3, respectively. All experiments were conducted according to a face-centered cube design. Under optimal conditions (4.79% of enzyme; 46.1 degrees C; 30.1 h), the incorporation of DHA into HLCO was 37.3%. The corresponding maximal incorporation of EPA (61.6%) into Laurical 25 was obtained using 4.6% enzyme, a reaction temperature of 39.9 degrees C, and a reaction period of 26.2 h. Examination of the positional distribution of FA on the glycerol backbone of modified HLCO with DHA showed that the DHA was primarily located in the sn-1,3 positions of the TAG molecules. However, lauric acid also remained mainly in the sn-1,3 positions of the modified oil. For EPA-modified Laurical 25, lauric acid was present mainly in the sn-1,3 positions, whereas EPA was randomly distributed over the three positions.