Lipid profile, volatile compounds and oxidative stability during the storage of Moroccan Opuntia ficus-indica seed oil

Abstract

The fatty acids, sterol, tocopherol and volatile compositions of Moroccan cold-pressed cactus (Opuntia ficus-indica) seed oil were studied. The most abundant fatty acid, tocopherol and sterol were linoleic acid (60.6%), γ-tocopherol (533 mg/kg) and β-sitosterol (6075 mg/kg), respectively. In this study, 23 volatile compounds were identified with perceivable odor attributes for 14 compounds. The oxidative quality of cactus seed oil was monitored over 4 weeks at 50 °C. Increases in PV, K232 and FFA were detected during the first two weeks as well as a decrease in the induction time; whereas no change was reported for the K270 values. The amount of total phenolic content increased until it reached 0.3 mg/kg and then decreased by the end of the storage period; while tocopherols started to decrease after the first week. The fat-free residue extracts showed a very strong effect to reduce the oxidation of linoleic acid. Consequently, the extracts were significantly more effective to bleach β-carotene in the β-carotene-linoleic acid assay in comparison with the control.

Keywords

• β-Sitosterol
• γ-Tocopherol
• Opuntia ficus-indica
• Oxidative stability
• Peroxide value