Abstract: In order to offer theoretical references for the application of millet starch and the screening of cultivars with good processing suitability, 9 major summer millet cultivars in China were selected to systematically study the granule morphology and size, chemical composition, iodine blue value, light transmittance, freeze-thaw stability, pasting properties, solubility and swelling power, retrogradation properties and other physicochemical properties of starches from these cultivars. The results showed that starch granules from each millet cultivar were single granules with a particle size in the range of 0.48—2.25μm and 3.50—29.32 μm. Starch granules were mostly polygonal though sometimes oval in shape, and displayed clear polarization cross. The different millet cultivars showed an obvious difference in the morphology of starch. The amylose content, iodine blue value, light transmittance, and syneresis rate of the tested millet cultivars were in the range of 2.91%—15.80%, 0.601—0.809, 4.4%—22.3% and 0.77%—62.23%, respectively, with significant differences among these millet cultivars. Moreover, significant differences in starch pasting properties, solubility and swelling power and retrogradation properties were also observed. Therefore, different millet cultivars are specifically suitable for different processing purposes.

Key words: millet, starch, size, pasting property, physico-chemical property