The composition of pigeon peas (Cajanus cajan (L.) Millsp.) grown in Botswana

This study investigated the composition of pigeon peas (Cajanus cajan), grown at Sebele, Botswana. The raw seeds of six varieties were analyzed for dry matter, crude fat, protein, fiber, and ash, using Association of Official Analytical Chemists procedures. Major minerals, Ca, K, P, Mg, Na and trace minerals, Cu, Fe and Zn were also assessed. The range of nutrient contents obtained were: dry matter 86.6-88.0%, crude protein 19.0-21.7%, crude fat 1.2-1.3%, crude fiber 9.8-13.0%, and ash 3.9-4.3%. Minerals ranges (mg/100 g dry matter) were: K 1845-1941, P 163-293, Ca 120-167, Mg 113-127, Na 11.3-12.0, Zn 7.2-8.2, Fe 2.5-4.7 and Cu 1.6-1.8. There were no significant differences in Na among the six varieties (p > 0.05). For the other components, varietal differences (p < 0.05) were observed. The values obtained for the dry matter, crude protein, fat, ash, Ca, Cu, Fe, and Mg were similar to those in pigeon peas grown elsewhere, while those for crude fiber and Zn were higher. In general, the composition of pigeon peas compared favorably with those of other legumes such as Bambara groundnut (Vigna subterranea). The levels of crude protein, crude fiber, K, Ca, P and Mg indicated that pigeon peas could be valuable in the diet of the people of Botswana. This crop would positively contribute protein in the diet and the diversification of agricultural produce.