Structural and physicochemical properties of ginger (Rhizoma curcumae longae) starch and resistant starch: A comparative study

The objectives of this study were to investigate and compare the structural and physicochemical properties of native ginger starch (NGS) and ginger resistant starch (GRS). NGS had oblate and compact granules, whereas GRS exhibited fissures. Compared to GRS, NGS had a narrower molar mass distribution and a higher molecular weight (Mw). According to X-ray diffraction measurements, Fourier transform infrared spectroscopy, and 13C CP/MAS NMR spectroscopy, NGS sample had an A-type crystalline pattern with high relative crystallinity and short-range order structure, and GRS had a B-type crystalline pattern. Furthermore, NGS exhibited significantly higher gelatinization enthalpy than GRS. NGS displayed lower peak viscosity and final viscosity, whereas GRS had higher through viscosity and final viscosity, presumably due to the content and type of resistant starch. The pasting and gelatinization properties of NGS and GRS might be related to relative crystallinity and short-range order structure. The information obtained from this study can be used by manufacturers and researchers in the production of ginger-containing products.