In this paper, the development of a Digital Twin of a beverages pasteurization system for temperature monitoring, using NI Lab-VIEW control system toolkit, is described. A cyber-physical production system, composed of a real-time simulation tool and a controller, has been set up and tested on a pilot plant set up in a university laboratory. The paper shows how the software platform, together with the hardware, has been implemented in a traditional system, not (yet) ready for Industry 4.0 technologies, and therefore underlines the main issues occurred during its development. The Digital Twin includes a CompactRIO controller and a set of probes, connected with the controller. The aim of the Digital Twin is to monitor the machine status, with a particular attention to the temperature reached by the service water and the required steam flow. To demonstrate the effectiveness of this system, a set of experimental tests has also been carried out.