Evaluation of Egyptian cottonseed, sunflower and canola Oils.

This study was carried out to evaluate the physico-chemical properties, fatty acid composition and unsaponifiable matter of sunflower, cottonseed and canola oils. The obtained results showed a slight variation in specific gravity and refractive index between the studied oil samples. Also, the results indicated that the color of cottonseed oil was darker or higher (5.4 red and 35 yellow) than the other oil samples. in contrast, the sunflower oil recorded the lowest value of color . Canola oil was recorded the highest acid value while the lowest value was observed in sunflower seed oil. The iodine values were 122.68, 110.30 and 109.00 for sunflower, cottonseed and canola oils, respectively. The cottonseed oil recorded the highest value of saponification (194.21) while the lowest value was noticed in canola oil (185.45). The peroxide value was 0.89, 6.65 and 1.75 meq. peroxide/kg sample in sunflower, cottonseed and canola oils, respectively. The highest TBA value was recorded in canola oil (1.20 mg malonaldehyde/kg sample). In contrast, the sunflower oil showed the lowest TBA value (0.21). The obtained results revealed that the investi- gated oil samples had a compara- ble content of unsaponifiable matter. The data of fatty acid composition revealed that Canola oil contains the lowest value of the TSFA while the cottonseed oil showed the highest value of TSFA .In contrast the cotton- seed oil contained the lowest value of TUFA while the sun- flower and canola oils recorded the highest value of TUFA, respectively. Unsaponifiable matters of sunflower oil were fractionated by GLC technique. It consisted mainly of hydrocarbons and sterols. The total hydrocarbons content was 23.35%. It could be arranged the hydrocarbons based on total hydrocarbon in a descending order as follows: C28 C23 C24 Cl6 C28 C26 C21, C30, C25, C22, CI8 and C14. The total sterols was 76.65% ß -sitosterol was the major sterol fraction followed by stigmasterol and campsterol.