Kinetics of starch digestion in sweetpotato flours from Papua New Guinean and Australian cultivars

Twenty-five sweetpotato cultivars from Papua New Guinea (PNG) and Australia were studied for their flour digestibility properties. The cultivars displayed monophasic digestograms, and a modified first-order kinetic model adequately predicted the rate and extent of starch digestion. Flours from all the cultivars had high average glycemic index (GIavg) and glycemic load (GL). This study of starch digestion in a wide range of sweetpotato cultivars demonstrates associations and interactions of non-starch components in the flours, and their effects on starch digestibility. The presence of resistant starch (RS) in some cultivars is highlighted with respect to its potential contribution to human health and nutrition.