Determination of the structural changes by FT-IR, Raman, and CP/MAS 13C NMR spectroscopy on retrograded starch of maize tortillas

► The nixtamalization, production and storage of tortillas (4 ± 1°C) caused many changes in starch structure, resulting in a increased crystallinity and higher content of resistant starch. IR analysis showed a band at 1047 cm−1. Using techniques as IR, Raman and CP/MAS 13CMNR spectroscopy on retrograded starch of maize tortillas stored for 10 days we found that lime treatment is promoting a more ordered structure, due to enhanced protein-starch interactions. The overall results of this study, suggests that nixtamalization affected the starch and protein structures of corn and also enhanced the protein-starch-lipids interactions. The increase of RS on tortillas stored for 10 days can reduce the glycemic response in humans. This feature is important for people with type 2 diabetes.