Cups are made from soft blue PE plastic with an internal geometry, presenting a challenge to a full UV illumination: long vertical walls (ratio of its height to diameter is 1.5), groves on walls and a porous white plastic seal at the bottom, fixed by a ring at its center. The cups are to cup 20l glass jars each 11 second, in groups of 10 awaiting it´s advance to a jar cupping mechanism on a vertical rail. Two competing UV sources (with focusing reflectors) have been used: amalgam doped high performance U-shaped low pressure Mercury lamp (load 1.5 w/cm, 30% UVC) and our UV flashlamp. Within the production time of 11 sec the sterilization goal of 3 logs was achieved only with our UV flash lamp with 4 pulses (750J/pulse) without heating cups. It took 40 sec to get the same sterilization with continuous UVC (254 nm) lamp. Energy consumptions were 3kJ for the flash lamp and 2.4 kJ for the Mercury vapor lamp.