Abstract: A method for pasteurizing a liquid product includes heating the liquid product to a pasteurization temperature, thereby killing micro-organisms, keeping it in a treatment chamber at the pasteurization temperature for a holding period, regulating a length of the treatment station based at least in part on its flow-rate, regulating a product volume within the treatment chamber by changing a level of a liquid product surface in the treatment chamber through, for example, addition and removal of sterile gas or vapor-forming medium in a partial chamber of the treatment chamber formed above the product surface, or changing a level of a product outlet in the treatment chamber.