However, the compactness of these primary crystallites was not less than that of the advanced crystallite (crystalline region). The relative size of the sub-crystalline region was higher in NP-LRS3,GP-LRS3, and ZP-LRS3 than in native starch and HAMS, with LRS3 showing the highest number. Given that the primary crystallite in GP-LRS3 and ZP-LRS3 might lead to inconspicuous peaks, the crystalline region did not generate diffusion diffraction peaks associated with the sub-crystal structure. The crystallinity of LRS suggests that it contains a higher content of ordered double helix structure than HAMS. It seems possible that amorphous amylose wa transformed to a double helix structure during the autoclaving and cooling processes, and that this in turn resulted in a more orderly crystallite. There was no significant difference in either the crystalline type or crystallinity between ZP-LRS3 and GP-LRS3. This means that these two purified methods have no influence on the crystal structure of resistant starch.