Modification of wheat flour functionality and digestibility through different extrusion conditions

Continuous innovation in foodstuff and their higher quality requirements force food industry to look for flours with new specific functionalities. The objective of this work was to modify wheat flour functionality by using extrusion. This treatment significantly affected hydration, emulsifying, thermal and pasting properties of wheat flours besides their susceptibility to enzymatic hydrolysis and their amount of resistant starch. Thermal enthalpy decreased as the extrusion severity increased, indicating a higher amount of gelatinized starch. Hydration properties significantly increased, specifically 5-fold water binding capacity and 9-fold swelling compared with untreated wheat flour. Emulsifying capacity and the free sugar content increased in parallel with the extrusion severity. The susceptibility to enzymatic hydrolysis increased and the amount of resistant starch (RS) decreased as the extrusion severity augmented. Overall, extrusion allows modifying wheat flour features but it is advisable to select adequate extrusion conditions to achieve the desirable functionality. (C) 2014 Elsevier Ltd. All rights reserved.