The subject matter of the invention is a process of dehydration of biological products using the pressurized drying method in which the product is treated with a gaseous medium the movement of which over the dried product is forced in a closed system under appropriate pressure, in the presence of a difference between the temperature of the medium circulating in the system and the temperature of the dried product until the product moisture content is reduced to the desired level, and in which the dehydration process is executed at a constant temperature of the atmosphere surrounding the material, preferably higher than its storage temperature but lower than the degradation temperature of its components.In accordance with the essence of the invention, the process is carried out in a dehydration chamber where the dried product is placed on drying trays arranged on at least one rack with shelves fitted with heating surfaces, whereby at the beginning of the drying process the gaseous medium is nitrogen at a temperature of 30° C. to 50° C., and at a pressure of 1.1 to 1.4 Pa inside the dehydration chamber, and the material undergoes two processes at the same time—the process of exposure to moving gas medium that flows through a biological product bed at super-atmospheric pressure and at a preset temperature from 30° to 50° and the process of desorption drying caused by the shelves heating surfaces.The subject matter of the invention additionally includes a device for dehydration of biological products (particularly foods) using the method according to the invention, constituting a physically and thermally closed system consisting of an airtight dehydration chamber fitted with a door and connected by means of ducts with a condenser, inside of which a heat exchanger is placed connected with a heat generator located outside the system and horizontal drying trays arranged one above another, such device being fitted with means of delivering the required gases and/or bacteriost
