As the name suggests the salad dryer is used to dry lettuce and other leafy vegetables. After they have been washed, the wet vegetables are transported to the drying machine and placed onto an air-permeable conveyor belt. Then, hot air is blown from below through the belt. This air was heated with residual heat, generated by other processes in your processing line. This makes this machine an energy efficient solution. Water in food which is not bound to food molecules can support the growth of bacteria, yeasts and molds (fungi). The term water activity (aw) refers to this unbound water. The salad dryer thermally dries the vegetable product to practically 0% adhering moisture. The less moisture remains on the product, the lower the water activity or aw value.