Determination of Nutritional and Anti-nutritional Composition of Three Varieties of Yam (Dioscorea spp.) Cultivated in Ekiti State

Yam occupies a central position in the food culture and agricultural economy of South West Nigeria, with Ekiti State being one of the foremost yam producing states in the country. Despite its dietary importance, comparative data on the nutritional and anti-nutritional profiles of different yam species cultivated in Ekiti remain limited. This study determined the proximate composition, mineral content, and anti-nutritional factor concentrations of three yam varieties, specifically Dioscorea rotundata (white yam), Dioscorea alata (water yam), and Dioscorea cayenensis (yellow yam), obtained from Ado-Ekiti Agricultural Market. Samples were peeled, sliced, and oven-dried at 60 degrees Celsius before milling into flour. Proximate analysis, mineral determination, and anti-nutritional factor quantification using standard methods were carried out. Results showed Dioscorea alata had the highest moisture content (72 percent, fresh weight basis) while Dioscorea rotundata demonstrated the highest starch content (79.3 percent, dry weight basis). Calcium oxalate, the primary anti-nutritional factor responsible for oral irritation, was highest in Dioscorea cayenensis (3.48 mg per 100g). Protein content was relatively low across all species, ranging from 6.4 to 8.2 percent. The study recommends combining yam consumption with protein-rich legumes to achieve dietary balance, and documents quality benchmarks for yam variety selection in Ekiti farming communities. Keywords: yam, Dioscorea, proximate composition, anti-nutritional factors, Ekiti.