Effect of Variety and Storage Duration on the Physicochemical Properties of Sweet Potato in Plateau State

Sweet potato (Ipomoea batatas) is an important root crop in Plateau State, North Central Nigeria, contributing to food security and income for smallholder farmers. Post-harvest quality changes during storage significantly affect its commercial value and end-use suitability. This study investigates the effect of variety and storage duration on the physicochemical properties of three sweet potato varieties, UMUSPO1, UMUSPO3, and a local landrace, stored under ambient conditions in a well-ventilated store in Jos for 0, 4, 8, and 12 weeks. Properties evaluated include moisture content, total soluble solids, reducing sugars, starch content, dry matter content, and beta-carotene content. Firmness was measured using a penetrometer. Results showed that all varieties experienced progressive moisture loss and sugar accumulation during storage. Beta-carotene content in the orange-fleshed UMUSPO3 declined by 35 percent over 12 weeks, while remaining significantly higher than the white-fleshed UMUSPO1 at all storage time points. The local landrace maintained the highest dry matter content throughout storage, making it potentially suitable for flour production. Results draw on recent literature on sweet potato post-harvest physiology and storage technology. Findings provide information for value chain actors, the National Root Crops Research Institute, and Plateau State agricultural extension services on variety selection and storage management for different end uses. Keywords: sweet potato, physicochemical properties, storage, beta-carotene, Plateau State