PURPOSE: Packed food is placed in a cylinder which is made of microwave-permeating synthetic fibers coated on its surface with silicone rubber, tightly closed on both ends, then radiated with microwaves to effect sterilization in a short time, preventing the package from bursting and deteriorating.

CONSTITUTION: Packed food 2 and water 6 are placed in the cylinder 1 of microwave-permeating synthetic fibers coated with silicone rubber on its inner or inner and outer surfaces and tightly sealed on both ends with a rigid and thick heat-resistant plastic plate 4 and bolt 5, irradiated with microwaves to effect sterilization of the product.