A continuous grain relator which was equipped with a vibrating tray at a va
riable slope was developed for sterilization of dry food ingredients. The d
oses necessary for soft-electron (low-energy electron) sterilization of ric
e, buckwheat, wheat, tea leaf and black pepper with this continuous rotator
were much lower than those with a batch-type grain relator and at almost t
he same level as the doses for gamma-ray sterilization. The results suggest
that the continuous grain rotator enables efficient soft-electron steriliz
ation.