Apparatus for forming plastic preforms into plastic containers includes a transport device for transporting the plastic preforms, wherein the transport device has a movable carrier on which a plurality of forming stations are arranged, wherein the forming stations each form a cavity having forming moulds configured to receive plastic preforms which are formable into plastic containers within this cavity when acted upon by a flowable medium and expanded. The forming stations further includes an applicator which acts upon the plastic preforms with the flowable medium, and at least one connecting line configured to guide the flowable medium to the applicator. The apparatus also has a sterilization device, whereby at least a section of this connecting line can be at least temporarily pressurized with a sterilization medium.