Physicochemical properties of some underexploited and nonconventional oilseeds

Abstract

Six nonconventional oilseeds, Bauhinia monandra, Bauhinia refescens, Caesalpinia pulcherrima, Cyperus esculentus, Hildergadia bateri, and Garcenia kola, were analyzed for their proximate composition, minerals, fatty acids, iodine values, acid values, saponification values, viscosities, refractive indexes, and specific gravity values. Their moisture content ranged from 3.8 to 9.8%. The crude protein values varied between 0.2% in G. kola and 26.6% in C. pulcherrima. The crude oil content ranged from 0.2% in G. kola to 30.8% in C. rufescense. The oilseeds were generally high in potassium (265 f 2.1 to 1050 f 4.2%) and sodium (100 f 1.4 to 260 f 1.4%). The fatty acid composition ranged from to Clg, including unsaturated Clg:~, C~W, and c18:3. The unsaturated fatty acids were predominant. Iodine values varied between 82.4 f 3.04 in H. bateri and 123.0 f 3.55 in C. pulcherrima. The saponification values ranged from 165.8 f 0.05 in H. bateri to 246.8 k 0.47 in C. pulcherrima. Acid values varied between 2.3 f 0.01 and 6.5 f 0.02 in the oilseeds. The viscosity values were low and, at 30 "C, values ranged from 13.18 f 0.03 cSt in B. monandra to 27.54 f 0.04 cSt in B. rufescens. The refractive indices and specific gravity values show littlevariation in the samples.