Characterization of Moringa oleifera Seed Oil Variety “Periyakulam 1”

Abstract

The oil from Moringa oleifera seeds variety Periyakulam 1 (PKM 1) from India was extracted using three different procedures including cold press (CP), extraction with n-hexane (H) and extraction with a mixture of chloroform:methanol (1:1) (CM). The oils were compared with those of a commercial virgin olive oil and Moringa oleifera var. Mbololo seed oil. The oil concentration ranged from 25.1% (CP) to 41.4% (CM). The density, refractive index, colour, smoke point, viscosity, acidity, saponification value, iodine value, fatty acid methyl esters, sterols, tocopherols (by HPLC), peroxide value, E^1%_{1 cm} at 232 nm and the susceptibility to oxidation measured by the Rancimat method were determined. The oil was found to contain high levels of unsaturated fatty acids, especially oleic (up to 71.60%). The dominant saturated acids were palmitic and behenic (both up to 6.4%). The oil was also found to contain high levels of β -sitosterol (up to 45.58%), stigmasterol (up to 23.10%) and campesterol (up to 15.81%). α -, γ - and δ -tocopherols were detected up to levels of 15.38, 25.40 and 15.51 mg/kg of oil, respectively. Moringa oleifera seed oil showed a long induction period (at 120°C), which however was reduced from 42.56 to 72.56% after degumming. The Moringa oleifera seed oil showed high stability to oxidative rancidity. Among the methods used for extraction, the mixture of chloroform:methanol (1:1) (CM) showed the higher resistance to oxidation.