The invention relates to a method of drying a material, that includes the steps of: providing a gaseous atmosphere with superheated steam in a housing, transporting a material into the housing, and drying the material in the gaseous atmosphere. Thereafter, transporting the dried material out of the housing and extracting from the gaseous atmosphere volatile substances which escape from the material into the gaseous atmosphere, especially flavors. The invention is also direct to an apparatus for drying the extruded material.

An apparatus and method for microwave vacuum-drying of organic materials, such as food products. The apparatus has a microwave vacuum chamber 20, a loading module 36 to load containers 38 of the organic material into the vacuum chamber, a rotatable cylindrical cage 64 in the vacuum chamber for rotating the containers, a piston 114 for moving the rotating containers through the vacuum chamber, and means for unloading the containers of dehydrated material from the vacuum chamber. The apparatus may include an equilibration chamber 150 for cooling the dehydrated material under reduced pressure, and a transfer module 42 to transfer the containers from the vacuum chamber to the equilibration chamber. The apparatus has a microwave transparent window 54 for transmission of radiation into the vacuum chamber, and a gas jet 58, 60, 62 for blowing a stream of gas, such as air or nitrogen, into the vacuum chamber adjacent to the window.

The invention relates to a method of drying a material, that includes the steps of: providing a gaseous atmosphere with superheated steam in a housing, transporting a material into the housing, and drying the material in the gaseous atmosphere. Thereafter, transporting the dried material out of the housing and extracting from the gaseous atmosphere volatile substances which escape from the material into the gaseous atmosphere, especially flavors. The invention is also direct to an apparatus for drying the extruded material.

An apparatus for drying a material is provided. The apparatus comprises a housing, a superheated steam generator, inlet and outlet ports disposed relative to the housing and an extraction unit for extracting volatile substances from the atmosphere within the housing.