User:MattAldred/TunnelPasteuriser

A tunnel pasteuriser is one form of

In tunnel pasteurisation bottles or cans are filled and closed in the normal way, then funnelled into the pasteuriser 'tunnel' before any labelling is added. The tunnel has a low ceiling with spray heads at regular intervals. Temperature controlled water is sprayed down on to the packages. The bottles or cans move through the pasteuriser slowly on either a walking beam or conveyor belt. The tunnel is divided into many temperature zones to slowly bring the product upto temperature, keep them at a specified holding temperature and then bring them back down to room temperature.

Modern tunnel pasteurisers contain sophisticated control systems to manage the temperatures, deal with line hold-ups and slow-downs in a way to prevent over or under pasteurisation of the product. Water is normally recirculated to improve energy efficiency; water is preheated by spraying onto hot bottles within the cooling zones, then the water is heated externally and sprayed onto the bottles within the pastuerising zones, before being cooled by spraying onto the cold bottles in pre heating zones. A run through the pasteuriser takes between 20-50 minutes at temperatures from 60°C to 90°C. Due to the length of time the bottles must be heated, tunnel pasteurisers can be extremely large. However, solutions are available with double deck designs to optimise the use of space.