Evaluation of technological and nutritional quality of bread enriched with amaranth flour

Abstract

The objective of this investigation was to develop bread, with high nutritional and technological quality, using whole flour of Amaranthus spinosus and Amaranthus hypochondriacus. Bread quality was analyzed in terms of chemical composition, loaf specific volume, width/height ratio of the central slice, crust/crumb color, crumb structure and firmness, and sensory analysis. Starch thermal properties were studied in terms of enthalpies of starch gelatinization during baking and amylopectin retrogradation during storage. Incorporation of amaranth flour significantly increased protein, lipid, fiber, ash, and myo-inositol phosphate contents. Bread with amaranth flours exhibited soluble/insoluble fiber ratios close to 1:2, which presents the most effective physiological action. Intake of products with high substitution of amaranth could cover the protein requirement in adults, and could contribute substantially to intake of dietary fiber, Fe, and Zn according to daily recommendations. Bread with A. hypochondriacus showed higher acceptability than formulations with A. spinosus. Inclusion of amaranth allowed delaying and decreasing crumb staling in terms of amylopectin retrogradation. The inclusion of amaranth could be limited to a maximum of 25 g/100 g, with considerable nutritional improvement and acceptable sensory and technological quality, even during the staling process.