Abstract
This study examined the effects of three pretreatments (parboiling [PB], microwave [MW], and vacuum microwave
[VMW]) on stress crack reduction and the microstructure of dried corn grains, using scanning electron microscopy (SEM)
and X-ray computed tomography (CT) images. Changes in microstructure and porosity were evaluated through image
analysis. The results revealed that MW treatment caused swelling and reduced starch cracks, while PB treatment led to the
collapse of starch structure. In contrast, VMW treatment resulted in minimal observable internal structural changes. These
differences in microstructure and porosity may be attributed to the varying distributions of hard and soft starch within the
corn kernels.
