Correlation between gelatinization enthalpies,water absorption index and water soluble index in grits, corn meals and nixtamalized corn flours.

Corn snack industry has empirically found that big and abundant blisters are developed when cornstarch is highly gelatinized, because of milling processes. This defect affects mainly the texture and appearance of the snacks. In the present study, gelatinization enthalpy by DSC was measured in grits, corn meals and nixtamalized corn flours, and correlated with Water Absorption Index (WAI) and Water Soluble Index (WSI), to generate an enthalpy prediction model. Results indicated that the more intense the process of milling was (lower particle diameter), the lower the gelatinization enthalpy values were. Grits presented a gelatinization enthalpy mean of 8.05 1.22 J/g, corn meals of 5.33 1.87 J/g and nixtamalized corn flours ranged between 2.35 y 3.28 J/g. The gelatinization enthalpy was significantly correlated with WAI and WSI (- 0.847 y - 0.763, respectively). A predictive model was successfully generated to predict gelatinization enthalpy in grits, corn meals and flours