Abstract: In this experiment, the effects of the alkaline, enzyme, SDS and Ultrasound starch extraction methods on the structure of japonica rice were studied from these aspects: starch morphology, amylose content, amylopectin molecular weight, distribu-tion of anhydroglucose chains from debranched amylopectin and so on. Then some conclusions were drawn: the effects of SDS and ultrasound extraction on the structure of rice are less than the alkaline isolation, but more than the enzyme isolation; compared with the amylopectin molecular weight of starch isolation by enzyme, the amylopectin molecular weight of starches isolation by alkaline and SDS were lower, and the long B chain content decreased, but the intermediate B, short B and A chain increased.

Key words: japonica rice, starch, structure, isolation