F.O. Oyedeji
Department of Chemistry, University of Ibadan, Ibadan, Nigeria
R.A. Oderinde
Department of Chemistry, University of Ibadan, Ibadan, Nigeria
ABSTRACT
Samples of crushed seeds and grains of fourteen vegetables-Zea mays, Penisettum americanum, Sorghum bicolor, Citrullus lanatus, Citrullus coloncythis, Cocos nucifera, Elaeis guineensis, Sesame indica, Theobroma cacao, Arachis hypogea, Butyrospermum paradoxum, Telefaria occidentalis, Mangifera indica and Irvingia gabonensis were extracted for their oils using isopropanol as solvent. The oils obtained were characterized by determining their physicochemical properties. The results obtained were: oil yields (3.7-61.0%); pH (4.00-6.28); specific gravities (0.812- 0.965); viscosities (5.52-108.03 Cs); refractive indices (1.435-1.477); acid values (0.66-86.02 mg KOH g-1 Oil); percentage free fatty acid (0.33-43.27); Saponification value (159.04-289.50 mg KOH g-1 Oil); ester values (91.65-287.90 mg KOH g-1 Oil); percent unsaponifiables (0.10-4.90); iodine values (13.5-135.4 WIJ`s) and peroxide values (1.7-19.4 mg Eq kg-1). These results show that the oils extracted with isopropanol had deep colours and odours and higher % unsaponifiables than oils extracted with regular extraction solvents like hexane and petroleum ether. Isopropanol extracted oils were also more viscous and showed increased stability as observed from longer shelf life and the fact that most of the oils did not have characteristic rancid odours even after storage at average room temperature (28oC) and ambient humidity for six years.
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How to cite this article
F.O. Oyedeji and R.A. Oderinde, 2006. Characterization of Isopropanol Extracted Vegetable Oils. Journal of Applied Sciences, 6: 2510-2513.
DOI: 10.3923/jas.2006.2510.2513
URL: https://scialert.net/abstract/?doi=jas.2006.2510.2513
DOI: 10.3923/jas.2006.2510.2513
URL: https://scialert.net/abstract/?doi=jas.2006.2510.2513
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