Study on Structural Changes of Starches with Different Amylose Content during Gelatinization Process

Abstract A thorough understanding of structural changes during gelatinization is extremely important for precise control of starch functional properties for food processing and human nutrition. Here five starches with different amylose content between 1.06% and 63.08% are selected to reveal the relationship between the structural changes and amylose content during starch gelatinization by Raman spectroscopy and X‐ray diffraction (XRD) in conjunction with a protocol using the rapid viscosity analyzer (RVA) to generate material for analysis. The results show that the high‐amylose starch has stronger resistance to gelatinization, and its long‐range order structure is more stable which is consistent with the conclusion that certain residual crystallinity remains after gelatinization. Meanwhile, the destruction of short‐range order structure is not significant compared with that in low‐amylose starch when the temperature reaches the pasting temperature. These phenomena are related to the fact that the high‐content amylose promotes the formation of the amylose‐lipid complex during the gelatinization by differential scanning calorimeter (DSC). The presence of the amylose‐lipid complex can restrain the swelling of starch granules and maintain their molecular structure during heating.