Techno-functional properties of wheat flour-resistant starch mixtures applied to breadmaking

Resistant starch can be used to reduce the availability of carbohydrates in baked products. In this study, the effect of type 4 resistant wheat starch (RS4) on wheat flour dough and breads was evaluated. Wheat flour was substituted by RS4 at 10%, 20% and 30% w/w (RS10, RS20 and RS30, respectively). Rheological and thermal behaviours of dough were evaluated. Besides, bread quality, starch digestibility and bread staling were analysed. All substituted dough exhibited viscoelastic behaviour but lower elastic and viscous moduli. Regarding to bread quality, specific volume and crumb texture were negatively affected in samples with RS4. However, all samples were technologically acceptable. During storage, crumb hardening was observed in breads without and with RS4 but amylopectin retrogradation was not particularly affected. The in vitro digestibility of bread with RS showed a lower release of reducing sugars and a lower estimated glycaemic index, suggesting a healthier profile for these breads.