Abstract

S. S. Audu^1*, M. O. Aremu² and L. Lajide³

DOI : http://dx.doi.org/10.13005/ojc/290318

The black turtle bean (Phaseolus vulgaris L.) is popular among the people of Bokkos in Plateau State, Nigeria where it is cultivated and locally known as “Kwakil”. The effects of different processing methods (boiling, cooking, roasting, sprouting and fermenting) were investigated on fatty acid composition, physicochemical parameters and antinutritional factors of black turtle bean seeds. All the analyses were carried out using standard analytical techniques. The results showed that oleic acid and linoleic acid were the most concentrated fatty acids in the raw and processed samples with values ranging from 27.7 to 30.8% and 54.7 to 64.0%, respectively. Capric, lauric and myristic acids were present in small quantities with maximum value of 1.6% in roasted sample. Unsaturated fatty acids predominated in all the samples with an adequate amount of essential fatty acids. Significant differences were observed (p<0.05) in the fatty acid compositions between the raw and processed seed samples. The results of physicochemical properties of the seed oils for all the samples showed mean range values of the following parameters: Saponification value (190.5 – 198.05 mg KOH/g), peroxide value (3.20 – 3.42 meq O₂/kg), iodine value (136.4 – 146.4 mg of I/100g, acid value (10.40 – 10.78 mg KOH/g), kinematic viscosity at 100^oC (8.12 – 8.44 mm²/s), specific gravity at 25^oC (0.96 – 0.97), unsaponifiable matter (3.37 – 3.62%) and flash point (302 – 315^oC). Generally, the values of the physicochemical parameters showed that the oils may be useful as edible oils due to their stability as frying oils. The results of antinutrients revealed that reductions were almost recorded in all the processed seed samples compared with the raw sample.

Black turtle beans;processing;fatty acids;physicochemicals;antinutrients

[ View HTML Full Text]