Abstract: Objective: To explore the effect of germination on molecular structure of starch from polished rice with germ. Methods: Scanning electron microscope (SEM), high performance liquid chromatography (HPLC), X-ray diffractometer (XRD) and Fourier transform infrared spectroscopy (FT-IR) were used to analyze the changes in surface structure, relative molecular weight distribution, crystallinity and characteristic structure of starch granules from germinated and non-germinated rice. Results: Compared with non-germinated rice, the surface microstructure of starch granules from germinated rice did not exhibited a significant change, but their molecular weight, crystallinity and IR transmittance revealed an obvious decrease, and the stretching vibration of O－H, C－H and C－ O bonds was enhanced. Conclusion: During the germination process, amylose and amylopectin are degraded, which results in an obvious change in molecular structure of starch from germinated polished rice with germ.

Key words: polished rice, germ, molecular structure, crystallinity, FT-IR