The analysis of X-ray diffraction and amylose relative crystallinity before and after heat treatment is presented in Figure 4 B Starch granules contain both crystalline and amorphous regions and their

The X-ray diffraction and amylose relative crystallinity analysis was presented in Figure 4 B before and after heat treatment. Starch granules contained both crystalline and amorphous regions, and their crystal type was commonly classified into four types: A, B, C, and V. As depicted in Figure 4 B, the starch in grains exhibited strong diffraction peaks at 15°, 17°, 18.1°, and 23.3°, indicating a typical A-type crystal structure. However, the original crystal structure of starch in noodles was disrupted after steaming, and the characteristic peak of A-type structure almost vanished. Instead, a weak and broad diffuse diffraction peak at 20° (2 θ) was observed, which could be attributed to the straight chain starch and lipids in wheat flour (de Dios Figueroa-Cárdenas et al., 2016). The OCT conditions resulted in a range of crystallinity between 3.15 % and 4.56 % for noodles cooked by different methods, with the highest crystallinity (4.56 %) achieved after baking (Figure 4 B). The decline in crystallinity was mainly attributed to the breakdown of hydrogen bonds between starch molecules caused by thermal treatment, as well as the unraveling of double helix structures (Wang et al., 2017).