Abstract: An apparatus for puffing granular material, in particular cereals and legumes, has a heating apparatus for preheating the granular material and a puffing reactor for puffing the material. For effective, fast, and uniform heating of the material, it is proposed that: the heating apparatus have a free jet fluidized bed without a flow impact floor in which a batch of the material to be heated can be acted upon, in a preheating operation synchronized with the puffing process and proceeding batchwise, by a heat-carrying gaseous medium.

Abstract: A drum cooker for cooking granular products comprises a vessel mounted to rotate about an axis. At least two nozzle groups are provided opening into said vessel. One of said nozzle groups is arranged in that it opens into a first area of said vessel covered by that granular product. A second nozzle group opens into a second area of said vessel not covered by said granular product. For enhancing the quality of the cooking process, a control means is provided for supplying said gaseous heat-carrying medium at any time to said nozzle group only that opens into that first area covered by said product.

Abstract: A device for puffing products such as foodstuffs or tobacco comprises an upright puffing reactor having a vessel for receiving product therein. The vessel has a wall provided with a plurality of openings. A chamber surrounds the vessel. The vessel has no openings in an upper section. A first pressurized heat-carrying agent is supplied to the chamber under a first pressure, and the agent flows from the chamber through the plurality of openings uniformly through the product disposed within the vessel. Shortly before the vessel is opened via an opening mechanism, a second agent having a higher pressure than the first pressure is supplied into the upper section above the product disposed within the vessel for providing a “propelling charge” behind the product.

Abstract: A device for puffing foodstuff comprises an upright puffing reactor having a vessel for receiving foodstuff therein. The vessel has a wall provided with a plurality of openings. A chamber surrounds the vessel. The vessel has no openings in an upper section. A first pressurized heat-carrying agent is supplied to the chamber under a first pressure, and the agent flows from the chamber through the plurality of openings uniformly through the foodstuff disposed within the vessel. Shortly before the vessel is opened via an opening mechanism, a second agent having a higher pressure than the first pressure is supplied into the upper section above the foodstuff disposed within the vessel for providing a "propelling charge" behind the foodstuff.

Abstract: A drum cooker for cooking granular products comprises a vessel mounted to rotate about an axis. At least two nozzle groups are provided opening into said vessel. One of said nozzle groups is arranged in that it opens into a first area of said vessel covered by that granular product. A second nozzle group opens into a second area of said vessel not covered by said granular product. For enhancing the quality of the cooking process, a control means is provided for supplying said gaseous heat-carrying medium at any time to said nozzle group only that opens into that first area covered by said product.