The effects of flour and protein preparations from amaranth and quinoa seeds on the rheological properties of wheat-flour dough and bread crumb

Abstract

The effects of amaranth and quinoa flours and protein isolates prepared from amaranth and quinoa seeds on the rheological properties of wheat flour dough and bread were studied using new recording instruments, the micro Z-arm mixer (for dough) and the SMS-Texture analyser (for bread crumb). The addition of 10% amaranth or quinoa flours did not cause significant changes in rheological properties. However, higher additions (20% and 30%) resulted in significant changes in stability, the degree of softening and elasticity. Substitution of wheat flour by amaranth or quinoa flours resulted in an increase of water absorption capacity. A significant reduction of specific volume and an increase of resistance to deformation (firmness) of the crumb of breads prepared from flour mixtures containing high percentages of amaranth or quinoa flours was observed. The addition of protein isolates did not significantly influence the main rheological parameters of dough, and bread crumb.