The cooling tunnel consists of an insulated casing with a conveyor belt. Fans blow cold air vertically from underneath the belt through the product layer.
The ambient air cooling tunnel is mainly used for high temperature steamed products, such as boiled potatoes. Cool air is sucked into the tunnel through a filter installation. Filters are available in several classifications, from normal to ultra-filtered air. The conveyor belt is also available with a continuous belt cleaning system.
The ambient air part of the cooling tunnel is generally supplemented with a mechanical cooling system where the product is cooled down further until it reaches a little above zero. Cooling elements with a systematic condensate drain ensure a low air temperature and optimal hygienic conditions.