Disclosed are an apparatus and a method for producing a sterilizing gas mixture from a gaseous first component as a continuous phase, particularly air such as sterile air, and a liquid second component as a dispersed phase, particularly a sterilizing agent such as hydrogen peroxide, at a predefined quantity ratio. The invention more particularly relates to an apparatus and a method for producing a mixture of air and vaporous hydrogen peroxide having sterilizing properties for use in molding, filling, and sealing packaging machines. The apparatus is characterized in that the top portion of a container (1) consists of an atomization and storage container (1.1) that extends into an evaporator container (1.2) below, at the discharge end of the container (1), the evaporator container (1.2) being equipped with a heating device (2). Furthermore, the atomization and storage container (1.1) encompasses at least one controlled atomizing nozzle (3; 3.1, 3.2) that has a connection for feeding the gaseous first component (F1) and a connection for feeding the liquid second component (F2'). Finally, a pressure regulation device (14) is associated with the container (1), said pressure regulation device (14) triggering the at least one atomizing nozzle (3; 3.1, 3.2) according to the requirements of the discharging device (30) and maintaining the predefined constant pressure (p2=pA) in the container (1) by feeding gaseous first component (F1) and liquid second component (F2') at a predefined quantity ratio (F1/F2').