A freeze dryer, also known as a lyophilizer, is a machine that removes water from substances by freezing them and then exposing them to a vacuum. This process is used to preserve food and other materials by removing the moisture that would otherwise cause them to spoil. Freeze dryers are also used in the pharmaceutical industry to produce drugs and other medical products.
Freeze drying has a number of advantages over other methods of drying. First, it is a very gentle process that does not damage the delicate structures of food and other materials. Second, freeze drying produces products that are very stable and have a long shelf life. Third, freeze drying does not require the use of chemicals or preservatives.