ABSTRACT

The kernel of sandbox tree (Hura crepitans L.') cultivated at Umudike Abia state, Nigeria was decorticated, seed removed and reduced to different particle size according to the central composite design (CCD) of the Response Surface Methodology (RSM). Oil from the samples was extracted using the solvent extraction method and N-hexane as solvent. Oil yield and physiochemical properties of the oil as well as vitamin E and carotenoid were determined. Data obtained from the experiment were subjected to the Response Surface Methodology analysis and optimization. The extraction time, extraction temperature and particle size were significant (P<0.05) on the yield, acid value, iodine value, saponification value, peroxide value, free fatty acid, smoke point, melting point, cloud point, flash point, moisture content, specific gravity, refractive index, vitamin E (tocopherol) and carotenoid value. Variability between the oils from the samples arose from terms of the process variables, variation from earlier works attributed to interspecies, method of experiment, reagent and geography of the plant material. Optimization analysis of experimental data showed that extraction time of 7.36 hours, extraction temperature of 52.50°C, and particle size of 602.00pm produced oil yield of 70.74%, acid value, iodine value, saponification value, peroxide value free fatty acid value, smoke point, melting point, cloud point, flash point, moisture content, specific gravity, refractive index, vitamin E and carotenoid values are of 22.02mgKOH/g, 21g/100g, 218.86mgKOH/g,1.30mgEq/kg, 11.08%, 202.13°C, 12.55°C, 6.56°C, 127.91°C, 0.64%, 0.91g/cm3, 1.80, 1.69mg/100g, 0.73mg/100g respectively. The iodine value of 20.31 g/100g indicates high level of saturated fatty acid. The low value of vitamin E and carotenoid observed were attributed to the interspecies, method of analysis, reagent and processing method, high saponification suggests that the oil is a good raw material for industrial applications. Ultimately, the physical and chemical properties of sand box seed oil as enumerated in this work make it a great potential as a nutritionally promising oil.