the stress occurred during drying by the moisture and temperature
gradients within the grain. The stress can cause internal cracks and
lead to grain breakage during milling. The amplitudes of the stress
and grain breakage are related to intense and prolonged exposures
to drying air. For the rehydrated rice samples, their images
illustrated that after rehydration the structure of all samples
became uniform. The research of Ogawa et al. (2003) also indicated
the similar result.