Technological Properties of Orange Sweet Potato Flour Intended for Functional Food Products as Affected by Conventional Drying and Milling Methods

The aim of this study was to evaluate the effect of drying temperature and grinding pattern on physicochemical, hydration, thermal, and pasting properties of orange sweet potato flour (OSPF) and to define its potential application in functional food products. Air convection drying temperatures (50 and 80 degrees C) and grinding patterns (shear and consecutive shear-impact) were evaluated. Hydration and pasting properties were influenced by the two factors and their interaction. Particle size and damaged starch content are significantly related to technological properties. The results indicated that drying at 80 degrees C and consecutive shear- impact grinding can produce thickening flours, while drying at 50 or 80 degrees C and shear grinding can produce flours with water retention suitable for gluten-free bread-type products with good antioxidant capacity. Additional knowledge provided by these findings is the importance of the combination of drying temperature and grinding pattern in the technological properties of OSPF.