The morphology of the starch granules was evaluated using a
scanning electron microscope (Shimadzu SSX-550). The starch
samples were suspended in acetone (1 g/100 mL) and a small
quantity of each sample was spread on the surface of the stub and
dried in an oven at 32 C for 24 h. The samples were coated with
gold and observed by SEM under an acceleration voltage of 15 kV, at
a magnification of 2000 and 5000.