Chemical and thermal properties of flours from germinated amaranth seeds

Abstract

Modification of the chemical composition of amaranth flours from Amaranth caudatus L. seeds with germination was studied. Seeds were sprouted at 30 °C for 0, 18, 24, and 48 h. Proximal composition, total phenolic content and antioxidant activity were evaluated. Further, changes in fatty acid and protein profiles and in amino acid composition due to germination were analyzed. In addition, modification in thermal properties of starch and proteins of amaranth flours were studied. Germination process increased protein, ash, water soluble carbohydrates, phenols contents and antioxidant activity, while reduced the amount of lipids. Proportion of P-globulins and 11S (62 kDa) decreased while the A-11S polypeptide (34 kDa) increased with germination. After 18 h of germination, respect to the control flour, lysine and aromatic amino acids and essential fatty acids content of flour significantly increased. Therefore, germination improved nutritional characteristics of amaranth flour turning it into a high nutritional food ingredient.