Effects of different heat treatment methods on physicochemical characteristics and in vitro digestibility of sweet potato flour and its application in meal replacement flour

This study examined the effects of various heat treatments on physicochemical properties, functionality, and starch digestibility of sweet potato flour. Heat treatments darkened the color but did not change the chemical structure. Solubility decreased and swelling power increased (17.3%-18.3%) with baking, frying, and microwaving, while extrusion and steaming had opposite effects. Rapidly digestible starch content increased (8.96%-41.91%) in all treatments except steaming, which reduced slowly digestible starch (61.81%-28.97%). Based on the analysis of these studies, using low-temperature baked and extruded sweet potato flour as the main raw material, combined with the concept of complete nutrition, supplemented by nutritious ingredients such as quinoa, oats, and whey protein, we have successfully developed two sweet potato meal replacement flours (SP-1 and SP-2) and found they had good brewing properties and showed shear-thinning behavior. This study provided theoretical basis for sweet potato deep processing and functional product development. PRACTICAL APPLICATION: This paper studied the effects of different heat treatments on sweet potato flour, and developed two meal replacement flour based on this, to provide a theoretical basis for the application of the sweet potato industry.