Effects of processing methods on fatty acid composition, physical and chemical properties of Moringa oleifera seed oil

Abstract

The study was carried out to establish the effect of processing methods on the quality of oil extracted from Moringa seeds. The oil was extracted from the raw and processed (Boiling for 90 minutes and soaking for 72 hours) (BS90min/72hours) seeds using a mini oil screw press extraction machine. The Gas Chromatography Mass Spectrometer GC-MS analysis of raw and treated Moringa seed oil indicated presence of four saturated (lauric, myristic, palmitic and arachidonic) and five unsaturated (palmitoleic, stearic, oleic, linoleic and linolenic) fatty acids. There was a consistent trend of reduction in the concentrations of both the unsaturated and saturated fatty acids in the treated samples compared to the raw samples. Oleic acid was most abundant of the unsaturated fatty acids in both the raw (88.792%) and treated (79.946%) Moringa seed oil. Myristic acid recorded the lowest concentration of the saturated fatty acids in raw (0.939%) and treated (0.7640%) seed oils. The peroxide value also increased from 0.03±0.00mg/mol/kg in the raw to 73.00±0.06 mg/mol/kg in the treated oils. The quality character of the Moringa oil with respect to high peroxide value recorded in the oil of the processed seed indicated reduced shelf life. This calls for further studies to explore and improve on its nutritional values for possible utilization as an alternative to fish oil in fish feed production.

Keywords: Dietary oil, saturated, unsaturated, extraction, fatty acid.