Evaluation of changes in physical and chemical properties, carbohydrate profile and in vitro digestion properties of isolated starch and flours from creole black maize during germination

In this study, the changes in physical and chemical properties, carbohydrate profile and in vitro digestion properties of isolated starch and flour from creole black maize during germination are investigated. The novelty of this work is the investigation of how the changes in carbohydrate profile are related to starch digestibility, including the isolation and characterization of nanocrystals with orthorhombic crystal structure (27 ± 5 nm length and 12 ± 1 nm thickness) confirmed by transmission electron microscopy and X-ray diffraction. During germination, sucrose serves as the first energy source, while glucose and maltose are released by partial hydrolysis and raffinose is produced from the degradation of the cell wall, which affects both sugar content and viscosity. The rapidly digestible starch increases on the third day of germination, while the slowly digestible starch predominates on the first and sixth day. The resistant starch decreases and corresponds to the crystalline fraction of starch (RS2).