Abstract: The effects of heat-moisture treatment (HMT)on the properties and carboxymethylation reactivity of waxy corn starch were studied. Results indicated that after the heat-moisture treatment, the granule morphology of waxy corn starch does not change and the polarized light remains, but there is some crack on the surface. Heat-moisture treatment does not change the crystal type of waxy corn starch, but its gelatinized temperature and amylose percent increase after HMT. The carboxymethylation reactivity of waxy corn starch decrease after HMT.

Key words: heat-moisture treatment, crystalline property, amylose percent, carboxymethylation reactivity