Physicochemical properties of starch obtained from Dioscorea nipponica / 中草药

ABSTRACT

Objective To study the medicinal plants of Dioscorea nipponica, the physicochemical pro-perties of starch in D. nipponica were investigated by means of various analytical methods. Methods D. nipponica starch was characterized by scanning electron microscope (SEM), X-ray diffraction, granule size analysis, DSC, and Brabender Viscograph system. Results Compared with tapioca and potato starch, the morphology of D. nipponica starch showed smaller particles, oval shaped, and dissimilar granules in size. The crystal type of D. nipponica starch was C-type pattern. The amylose content in D. nipponica starch was 26.3%. The starch separated from D. nipponica showed the highest transition temperature and intermediate enthalpy of gelatinization between potato and tapioca. According to the viscosity measurement with Brabender viscograph, D. nipponica starch exhibited lower peak viscosity, higher setback and lower breakdown viscosity. Conclusion D. nipponica starch is obtained from D. nipponica. Significant differences from D. nipponica and other tuber starches in physicochemical properties are obtained due to their geographical origin.