Apparatus and method for on-line internal siliconing of glassbottles including a baking station for baking the siliconedbottles； wherein a siliconing station includes a supportdesigned to selectively receive one bottle at a time, aninjection device facing towards an inlet opening of thebottle, a mobile device for selectively blocking the injectoragainst the inlet opening of the bottle, a selective feedingdevice for feeding filtered compressed air and liquid siliconeto the injector, the injector being provided at the front,towards the support, with a drainage channel communicatingwith the inlet opening of the bottle； an emitter to sendtowards a sensor and through the bottle on the support a beamof electromagnetic radiation； and a control unit toselectively inject into the bottle a mixture of silicone andcompressed air or compressed air only and to process anelectrical signal emitted by the sensor to control theselective feeding device and/or a manipulator to discard anydefective bottles.
