Effect of microwave treatment on the structural and physicochemical properties of amylose partially removed sorghum starch.

This study aimed to probe the influence of amylose in starch granules on starch modification. Part of the amylose from sorghum starch was removed through warm water leaching, and the samples were then microwaved. The effects of treatments on starch structure, physicochemical properties, and digestibility were researched. Compared to sorghum starch without partial amylose removal, warm water leaching of amylose resulted in deeper concavity of sorghum starch granules and lower crystallinity, short-range ordering, setback and breakdown values, which disrupted the structure and thus rendered the starch granules more susceptible to microwave radiation, amplifying the advantages of microwave-modified starch. In addition, the ordered arrangement of amylose and amylopectin structures within the microwave-treated sorghum starch with pre-removed amylose were more readily disrupted, allowing enzymes to pass through more readily, thus increasing the fast-digestible starch content and digestibility of the starch. In summary, partial amylose removal can be used as a pretreatment method for modifying and expanding starch utilization in food and non-food industries while providing a new idea for developing baked foods.