Method for media supply through a thermal treatment plant (1) for a liquid product (P), preferably a drink, comprises: (a) ejecting a first aqueous medium from the treatment plant through an output product line (5) with the help of a second aqueous medium, (b) closing the output product line, and (c) optionally opening the output product line, so that the second aqueous medium can inflow into the product line, where a trigger (TS2) for opening the output product line is calculated based on the volume determined in the step (a) and a nominal capacity of the treatment plant. Method for media supply through a thermal treatment plant (1) for a liquid product (P), preferably a drink, comprises: (a) ejecting a first aqueous medium from the treatment plant through an output product line (5) with the help of a second aqueous medium, where the volumes of the second aqueous medium introduced into the treatment plant is calculated, preferably in the form of a continuous volume count; (b) closing the output product line, so that the second aqueous medium cannot flow into the product line, where a trigger (TS2) for closing the output product line is calculated based on the volume determined in the step (a) and a nominal volumetric capacity of the treatment plant; and (c) optionally opening the output product line, so that the second aqueous medium can inflow into the product line, where a trigger (TS2) for opening the output product line is calculated based on the volume determined in the step (a) and a nominal capacity of the treatment plant. An independent claim is also included for a device for media supply in a thermal treatment plant for a liquid product, preferably a drink, comprising: a volume measuring device for measuring a liquid volume led through the treatment plant; a output product line to further line of the treated product in the direction of a downstream production unit, preferably a product storage tank; a blocking device to close or open the output product lin