Comparative assessment for nutritional and antinutritional qualities revealed better performance of traditional white-fleshed sweet potatoes than orange-fleshed sweet potatoes

Abstract

Recent introduction of beta-carotene rich orange-fleshed sweet potatoes (OFSP) has resulted to consumers’ low demands for traditional white-fleshed sweet potatoes (TWFSP), without due consideration of their nutritional qualities. This study appraised the nutritional compositions of OFSP and TWFSP. They were analyzed for mineral content, antinutrients, and phytochemicals at National Root Crops Research Institute, Umudike. The field experiment was conducted using randomized complete block design with three replicates. TWFSP showed higher concentrations of minerals, anti-nutrients and phytochemicals than OFSP. In TWFSP, potassium ranged from 1879.20 ± 0.01 mg kg^-1 (‘B₃V₃’) to 1960.30 ± 0.01 mg kg^-1 (‘B₂V₂’) while in OFSP it varied from 1162.60 ± 0.02 mg kg^-1 (‘B₂₆T₂₆’) to 1800.20 ± 0.01 mg kg^-1 (‘B₁₀T₁₀’). The antinutrients and phytochemicals results showed that flavonoids in TWFSP ranged from 0.30 ± 0.01 mg TAE kg^-1 (‘B₁V₁’) to 970.50 ± 0.02 mg TAE kg^-1 (B₃V₃) while it varied from 0.20 ± 0.01 mg TAE kg^-1 (‘B₄T₄’) to 670.30 ± 0.01 mg TAE kg^-1 (‘B₈T₈’) in OFSP. Heritability estimates were high for all antinutrients and minerals while genetic advance was high only for potassium (42.206) and phosphorus (10.288) traits. Variation between phenotypic coefficient of variation and genotypic coefficient of variation was negligible, with the former higher for most minerals and antinutrients. TWFSP were found richer than OFSP, and suggests improvement by selection.