Formulation and characterization of vegetable oil blends rich in omega –3 fatty acids

Seven blends of vegetable oils were formulated from flaxseed, olive and canola oils differing in their content of n–6 to n–3 and n–9 to n–6 to n–3 fatty acids (FAs) ratio. FA composition, oil classes, triacylglycerol fractions and identity characteristics of the original three oils and their seven blends were determined. Results showed marked differences in the FAs composition between the three oils used for preparing the seven oil blends. The prepared blends had n–3 to n– 6 FAs ratio which varied from 1.2: 1 to 1: 9.1 with the highest ratio of n–3 to n– 6 FAs in flaxseed – canola oil blends. Increasing the level of canola oil in canola - olive oil blends increased from the linolenic acid and lowered from linoleic acid. Meanwhile increasing the proportion of olive oil in the vegetable oil blends was associated with a decrease in iodine value, linolenic acid, n–3 to n–6 and saturated to unsaturated FAs ratio. The opposite trend was noticed with increasing flaxseed and/or canola oil in such blend. Slight differences were observed in the specific gravity, refractive index and saponification values. Among the formulated blends, triacylglycerols were the major fractions of three oils and their seven blends. Also, the triacylglycerols of flaxseed and canola oil blends were fractionated into 9 groups rich in unsaturated triacylglycerols.