Physicochemical properties of the oils extracted from major canola cultivars grown in Iran

The current major cultivars grown in Iran [Okapi(O), Hyola 401 (H), Zarfam (Z), and Talayeh (T)] were supplied from the production areas [Khorasan Razavi (K), Golestan (G), Mazandaran (M), Tehran (T), and Fars (F) provinces], and their oil fractions were extracted after drying. The oils were composed of 7.2-8.0% saturated fatty acids, 61.7-67.4% monounsaturated fatty acids, and 23.6-29.3% polyunsaturated fatty acids. Except for the oils from Z-T and H-G cultivars with peroxide values of lower than 1.2 meq/kg, the oils from the other cultivars had peroxide values of higher than 2.0 meq/kg. The highest and lowest iodine value was found for the oils from T-K (109.6), and O-K (104.2) and H-G (104.8), respectively. Unsaponifiables matter content ranged from 3.4% (O-K) to 8.6% (H-G). The oil samples were contained 1.6% sterols on average. The oils from Z-K and O-K cultivars had the greatest tocopherols content (793.4 and 765.1 ppm, respectively), and the lowest contents were found in the oils from T-F (573.6 ppm) and H-M (556.0 ppm) cultivars. Phenolics, wax and total polar compounds contents were in the ranges of 23.8 ppm (T-F) and 127.3 ppm (H-M), 5.6% (O-K) and 10.8% (Z-T), and 2.2% (O-K) and 13.0% (T-F), respectively. The oil samples had densities, viscosities and refractive indices of 806.1-820.0 kg/m3, 96.3-104.2 cP, and 1.464765-1.467888, respectively. Oil/oxidative stability indices were according to the following order: H-G = Z-T > O-K > Z-K > H-M = T-F > T-K.