Effect of High-amylose Maize Starch at Different Heating Temperatures on the Pasting Properties, Gelation Behaviors and Anti-digestibility of Whole Wheat Flour

This study investigated the effects of high-amylose maize starch (HA) on the pasting properties, gelation behavior, and anti-digestibility of whole wheat flour (WWF) under different high-temperature cooking conditions. Composite flours were formulated by incorporating varying ratios of HA into WWF, with the protein content standardized at 13.8% through gluten adjustment. The composite flours were evaluated for farinograph properties and pasting behavior, thermal characteristics, gel hardness, and digestibility following heat treatments at 100 ℃ and 140 ℃. Results demonstrated that the addition of HA increased water absorption and reduced dough development time. Wheat starch (WHE) in WWF could gelatinize and form a gel network at temperatures below 100 ℃, while HA largely retained its granular form. At 140 ℃, HA could be fully gelatinized, with its granular structure completely destroyed. Notably, gel hardness did not show a consistent trend of reduction with increasing HA content. The enthalpy values of amylose-lipid complexes (ALC) in HA and WWF were determined to be 3.2 J/g and 1.9 J/g, respectively. However, no significant changes in enthalpy values were observed in the composite flour after the addition of HA. The RDS content of the composite flour decreased significantly compared to WWF (P<0.05) and the sum of SDS and RS content was greater than the theoretically expected value after treatments at 100 ℃ and 140 ℃. Therefore, the addition of HA could enhance the anti-digestibility of the starch of the composite system more effectively than its own anti-digestibility effect.