Concentration of omega 3-polyunsaturated fatty acids of seal blubber oil by urea complexation: optimization of reaction conditions

Production of omega-3 fatty acid concentrates from seal blubber oil (SBO) was optimized. In this process, the content of total ω3-fatty acids, Y1; eicosapentaenoic acid (EPA), Y2; and docosahexaenoic acid (DHA), Y3 in the final product was maximized. A three-factor central composite rotatable design (CCRD) was used to study the effect of urea-to-fatty acid ratio (X1), crystallization time (X2), and crystallization temperature (X3). Second-order polynomial regression models for Y1, Y2 and Y3 were employed to generate response surfaces. Under optimum conditions the maximum amount of total ω3 fatty acids (88.2%) from SBO was obtained at a urea-to-fatty acid ratio of 4.5, a crystallization time of 24 h, and a crystallization temperature of −10°C. ©