According to the present invention a method and apparatus for the sterilization of packaging materials is disclosed for use in automated packaging of food products. The low intensity ultraviolet radiation used is concentrated on the packaging material and capable of being positioned in close proximity thereto without resulting in heat damage. Low intensity ultraviolet is less dangerous with respect to the operator and effective shielding may be achieved easily. This method and apparatus is particularly suited for incorporation into automated packaging apparatuses which use preformed containers and series of interconnected lids for sealing of the containers. The invention will be of particular benefit to the packaging of dairy products where an extended shelf life is desired.