Abstract
In the present report, the fatty acids, tocopherols, and sterol profiles as well as the total phenolics and carotenoids of rosehip (Rosa canina) seed oil were determined. The major fatty acids in the oil were linoleic and linolenic acids, comprising 54.80% and 23.47% of the total fatty acids, respectively. Other bioactive lipids in the oil included total tocopherols (786.3 mg/kg), total phenolics (37.97 mg/kg) and total carotenoids (218.8 mg/kg). Rosehip oil was rich in gamma-tocopherol (472.0 mg/kg) and beta-sitosterol (78.0% of total sterols). The DPPH center dot (2,2'-diphenyl-1-picrylhydrazyl) radical scavenging activity of the oil showed 1.08 mg alpha-tocopherol/g oil and 4.18 mu mol TEAL (Trolox equivalent antioxidant capacity)/g oil, respectively. The ABTS(+) (2,2'-Azino-bis-3-ethylbenzothiazoline-6-sulphonic acid) radical scavenging activity of the oil showed 1.00 mg alpha-tocopherol/g oil and 3.02 mu mol TEAC/g oil, respectively. The induction period (IP) of the oil was 3.46 h for the Rancimat test (110 degrees C), while the IP of oil in differential scanning calorimetry (DSC) test (100-150 degrees C) ranged between 0.26 and 58.06 min. The oxidative stability of the oil was determined under thermal and photo oxidation conditions. The progression of oxidation at 30 degrees C (under UV light) and at 60 degrees C (in the dark) was followed by recording the ultraviolet absorption (K-232 and K-270) and degradation of total tocopherols, gamma-tocopherol and total carotenoids. Rapid deterioration occurred in the oil stored under UV light conditions. The information provided in the present work is of importance for using rosehip seed oil in different food and non-food applications.