Physicochemical characteristics analysis in Niger seed edible oil (Adama) and Linseed edible oil (Bishoftu)

Abstract

This study was directed towards the characterization of Niger and Linseed oil purchased from Adama and Bishoft respectively using official methods. The AOAC method of analysis was employed in the determination of the chemical and physical properties of the oils. The chemical properties of the oils determined included the saponification value, acid value, peroxide value, Soap content, Copper (Cu) (mg/kg) and Iron (Fe)(mg/kg), and Insoluble impurities (%(m/m)). The physical properties of the oils determined were moisture content and volatile matter at 1050C (% (m/m)), refractive index at 400C and Relative density at room temperature. The values obtained were Saponification values (192 & 189.17mgKOH/g), peroxide values(3.59 & 3.19 milliequivalent peroxide Oxygen/Kg oil), acid values (0.45 & 0.59 mgKOH/g), Soap contents (0.001 & 0.005 (%( m/m)), Copper (Cu) (not detected mg/kg), Iron (Fe)(not detected mg/kg), Insoluble impurities (0.01 & 0.02 %(m/m)), refractive indexes (1.4757 & 1.482 ), and Relative density at room temperature (0.9220 and 0.929) for Niger and Linseed oil respectively. One proximate composition obtained was moisture content (0.09 & 0.15%). From the results obtained it can be concluded that Niger and Lin seed oils have huge potentials for use as domestic oils.