Structural and quality evaluation of soy enriched functional noodles

Physicochemical and functional properties of refined wheat flour (RWF), soy flour (SF), sorghum flour (SGF) as well as multigrain flour (MF) prepared with a blend of RWF (62.2%), SGF (24.6%) and SF (13.2%), were evaluated in relation to their noodles making potential. Results showed that MF did not differ significantly from RWF for its bulk density, swelling, water absorption and oil absorption capacity. However, the solubility score improved significantly (P <= 0.05) in the multigrain sample. Multigrain noodles showed a significant (P <= 0.05) improvement in nutritional and antioxidant profile when compared to refined wheat noodles. The glycemic index (GI) of refined wheat noodles was found to be 39 +/- 0.1 which decreased significantly to 31 +/- 0.1 for multigrain noodles. Cooking time, cooking loss and hardness values increased significantly for multigrain noodles as compared to refined wheat noodles. Scanning electron microscopy of multigrain noodles showed a more compact structure with less space between starch granules compared to the control noodles. FTIR showed the presence of identical functional groups (C-O-H, N-H, C-N, C=O, and O-H) in both the control and multigrain noodles samples, with higher intensity of absorption for multigrain noodles.