The Effect of Microwave on the Physical and Chemical Properties of Cassava Starch

Starch is a kind of natural polymers and belongs to the renewable resources. Starch grain in the interior has crystallization area and non-crystalline area where the chemical reactions occur. In this paper, the effect of microwave cassava starch on the physical and chemical properties and characterizated by infrared spectrum and scan electrical microscope (SEM) was investigated. The transparency increase, the viscosity reduce and the anti-sedimentation enhanced after microwave action on tapioca starch. The result of infrared spectrum and scan electrical microscope shows that the original basic structure of cassava starch by microwave has not been damaged but the crystalline structure has been destroyed, which results in the reducing of the crystallinity of starch, the increasing of the contact area of particles and reaction reagents and the improving of the reaction activities .