Production and Characterization of Type III Resistant Starch from Native Wheat Starch Using Thermal and Enzymatic Modifications

Abstract

The most widely employed methodologies for type III (retrograded) resistant starch formation is a cyclic heating-coolingtreatment or its combination with a previous enzymatic debranching step. In this work, two retrogradation temperatures, 0 and4 °C, were evaluated for obtaining type III resistant starch from non-debranched and pullulanase-debranched wheat starch. Thestarches were characterized by their thermal and pasting behavior. Also,microstructural and crystalline aspects were related to theproduction process and the nutritional properties of the products. The most influencing factor for resistant starch formation wasthe application of the pullulanase-debranching step previous to the cyclic treatment. This led to a higher starch retrogradation anda more compact microstructure, which decreased the thickening capacity and the digestibility of the starches. Then, even thoughall the obtained starches exhibited lower digestibility, the pullulanase-debranched ones presented the lowest estimated glycemicindex (ca. 34%), showing the highest yield of resistant starch formation. Finally, this work presents a concise protocol forobtaining type III resistant starch enriched powder with low digestibility that could be used in the formulation of different healthyfoods such as dairy products, cereal bars, and even drinks.