Abstract
Cowpea is a legume rich in protein, B vitamins and minerals (magnesium, zinc), but also in antinutritionalfactors such as α-galactosides and phytic acid. The nutritional composition of cowpea seeds is thereforea criterion that can be taken into account to improve varietal selection.The nutritional composition of 13 varieties of cowpea cultivated in Burkina Faso was characterised inorder to suggest varietal selection criteria based on nutritional potential. Nine varieties were cultivated inTenkodogo (T), 10 in Kamboinsé (K), and 6 in the two localities. Protein contents were determined by theKjeldahl method, the mineral contents by ICP-OES, thiamin contents by UHPLC-FLR, phytic acid contentsby HPAEC-CD and the α-galactosides and low-molecular-weight oses contents were quantified byHPAEC-PAD. Variance analysis allowed to evaluate the varietal effect from the results obtained by locality(nT=9, and nK= 10), and the crop site effect (plot) from varieties cultivated in the two localities.The protein contents of the samples studied vary between 19,9 and 26,2 g/100 g DM depending on thevariety. The phytate contents are higher on the Kamboinsé plot (with results ranging from 0,70 to 1,17 gIP6/100 g DM) than those of the Tenkodogo plot (0,42 to 0,80 g IP6/100 g DM). Thiamin equivalentcontents, ranging from 0,34 to 0,73 mg/100 g DM, showed a significant variety and plot effect. The mainforms of thiamin (di-phosphate and hydrochloride thiamins) are in variable proportions depending on thevariety and the plot. Iron and zinc contents are affected by the variety and vary between 3,70 to 5,92mg/100 g DM and from 3,30 to 5,14 mg/100 g DM. The total α-galactoside contents, which are between3,27 and 6,09 g/100 g DM, and the saccharose contents ranging from 1,29 to 5,80 g/100 g DM wereinfluenced by the variety effect. All of these components are influenced by the interaction between varietyand plot.These results of nutritional composition should be related to practices to identify processes decreasingantinutritional factors (α-galactosides, phytic acid) while taking account consumers preferences. Phyate,iron, zinc, thiamin, α-galactoside contents could constitute additional criteria in varietal selection ofcowpea, in Burkina Faso.