4 Dryers y rying of vegetables is still the most widel here are several options open to the dehydrator as to the type of dryer that can be used for this purpose. In the early days of the industry, tunnel and stove dryers were in general use. Designs varied widely but all of them involved the use of shallow trays upon which the material for drying was spread to a depth of 25-40mm. The tray loading and unloading involved a fairly high labour content but, in spite of this, many factories throughout the world are still using this method Continuous conveyor band dryers with single or multi-pass have however, superseded tray drying in recent years, and this trend towards automation has obviously brought a higher degree of efficiency into modern hydration factories and has substantially reduced the labour content of the Cabinet dryers are still useful, however, for pilot runs, and for specialised products where a high level of throughput is not desired or possible. This type of dryer is, therefore, described in this chapter, as it could well fill some special requirement, albeit not in the context of the main roduction line STOVE AND CABINET DRYERS Stove dryers are ideal for small to medium levels of Production, and are a smaller version of the tunnel dryer, in that they operate a system of tray drying, the trays being racked on mobile trucks. The air-flow, however, is4 Dryers Air drying of vegetables is still the most widely used methodand there are several options open to the dehydrator as to the type of dryer that can be used for this purpose. In the early days of the industry, tunnel and stove dryers were in general use. Designs varied widely but all of them involved the use of shallow trays upon which the material for drying was spread to a depth of 2540mm. The tray loading and unloading involved a fairly high labour content but, in spite of this, many factories throughout the world are still using this method. Continuous conveyor band dryers with single or multi-pass have, however, superseded tray drying in recent years, and this trend towards automation has obviously brought a higher degree of efficiency into modern dehydration factories and has substantially reduced the labour content of the operation. Cabinet dryers are still useful, however, for pilot runs, and for specialised products where a high level of throughput is not desired or possible. This type of dryer is, therefore, described in this chapter, as it could well fill some special requirement, albeit not in the context of the main production line. STOVE AND CABINET DRYERS Stove dryers are ideal for small to medium levels of production, and are a smaller version of the tunnel dryer, in that they operate a system of tray drying, the trays being racked on mobile trucks. The air-flow, however, is 65