Effect of cooking on the Nutritional Contents and Phytoconstituents of <i>Vigna Subterranea [L.]Verdc.</i>

Abstract

This research was carried out to assess the differences in the nutritional content and phytoconstituent of Bambara nuts(Vigna subterranea [L.] Verdc.)  before and after cooking. Samples were collected and analysed according to the standard methods. The proximate composition of the raw sample  revealed the percentage of moisture content, 7.93 %; crude protein, 22.49 %; crude fiber, 7.51 %; crude lipid, 8.45 %; ash content, 5.68 % and nitrogen-  free extract, 47.94 %. While the cooked sample had moisture content, 10.72 %; crude protein, 20.88%; crude fiber, 3.97 %; crude lipid, 15.13 %; ash  content, 3.28 % and nitrogen- free extract, 42.86 %. The lower value of crude protein in the cooked sample as compared to the raw could be as a result of  leaching of soluble proteins into the cooking water indicating that food processing may influence the availability of nutrients either positively or  negatively. From the phytoconstituent analysis, it was observed that the values of tannins, flavonoids, saponins, steroids, phytates, alkaloids and oxalates  reduced significantly (??< 0.05) by cooking. Furthermore, the correlation coefficient were carried out on the data generated and it was found  that the nutritional contents were negatively correlated (p < 0.05, r = -0.9) with most of the phytoconstituents which indicated that cooking makes the  nuts safe for eating.