Abrehem Abad - October 2
Importance of Minor components to the Oxidative Stability of camelina, chia, and sophia seed oils
The oils from camelina, chia, and sophia were extracted from their respective seeds. The resultant oils were subsequently chromatographically stripped of their minor components. The fatty acid profiles as well as the tocopherols present in the oils were analyzed. The stripping process effectively removed all coloured material as well as the tocopherols from the three oils tested. Meanwhile, oxidative stability of the oils as such or following stripping was determined. Both primary oxidation products, as conjugated dienes (CD), and secondary oxidation products, as thiobarbituric acid reactive substances (TBARS), were monitored over a 7-day period under Schall oven condition at 60C in a forced air oven. The fatty acid compositions of the oils did not change to any measurable extent upon stripping. The tocopherols in original oils were dominated by beta-/gamma- tocopherols (camelina 677.40, chia, 282.68, and sophia, 977.52±4.37 mg/kg) that were not separated and with lesser amounts of delta- and alpha- tocopherols. Meanwhile, all stripped oils were devoid of any tocopherol. The oxidative state of the oils indicated that stripped oils were significantly less stable than their unstripped original counterparts. The removal of tocopherols might contribute greatly to this destabilizing effect. Meanwhile, photooxidative stability of oils indicated that stripped oils were more stable than their original counterparts. Involvement of chlorophylls as photosensitizers appears to be exerting a dominant effect. Therefore, these oils, similar to extra virgin olive oil, must be protected from light by using tins or dark bottles in order to retain their health promoting minor components and prevent off-flavour development.