LOW TEMPERATURE DRYING WITH HEAT PUMPS NEW GENERATIONS OF HIGH QUALITY DRIED PRODUCTS

Abstract Heat pump dryers have found their application in drying of heat sensitive materials due to the possibilities of controlling drying conditions. In addition, this technology is energy saving and more environmentally friendly than direct heated dryers. In Norway, research on this technology has taken place over a period of 20 years and several industrial applications are seen, like drying of fish and vegetables. Several products have been dried in test plants, like fish products, fruits, vegetables, dairy products, biological active products and other heat sensitive materials. For such products quality can be controlled, like color, taste, bulk density and rehydration properties.