Chemical Evaluation of Oils Extracted from Seven New Varieties of Canola

Today one of the problems concerned with the agriculture and food industries is the import of approximately 90% of edible oils. It is therefore important to identify the chemical nature of an oil particularly the fatty acid composition in order to select the best quality. The aim of the present work is to evaluate seven different varieties of Canola and select the most suitable.
Seven different varieties of canola were obtained from Institute of Seed Improvement, Karaj Station. The seeds were subjected to oil extraction by solvent followed by the chemical analyses of the extracted oils namely fatty acid composition, induction period determination, quantitative determinations of Copper and Iron, quantitative determination of nonsaponifiable matter and qualitative and quantitative determinations of sterols and tocopherols.
The amount of the extracted oils for all the varieties examined ranged from 33.0 to 46.2%. The nansaponifiable matter content accounted for 1.88 to 3.10% where sterols were the major fraction. Tocopherols namely γ and α tocopherols were present but there were quantitative variations concerned with sterols and tocopherols in all the varieties examined. Mono and Poly unsaturated fatty acids concentrations ranged between 59.40 to 66.02 and 25.59 to 31.21 respectively among the varieties examined.
All the varieties examined had significant differences concerned with the chemical analyses. Oleic acid was the major fatty acid and traces of erucic acid were present among the examined varieties. All the crude extracted oils had induction periods ranged between 8.75 to 12.32 hours at 110˚C that might be considered satisfactory considering the fatty acid composition.