Abstract: Using the SEM and polarized light microscope analytical method, the structure characteristics and degrade process of potato starch in non-crystallized granule state were investigated. It was found that in non-crystalline process, blowing out opening with big and deep slot were formed because of the“ blowing out” way of swelling from inside to out. Starting from the blowing out opening starch granules, the starch granules were degraded deeply by α-amylase along the blowing out opening until complete disappearance. Native starch with compact crystallized structure, because of having no opening on the surface of starch granules, α-amylase degrade activity was much less than that of starch with non-crystallized granule state.

Key words: potato starch, non-crystallized granule state, structure characteristics degrade activity