U.S. Patent 5,299,583, assigned to Koerber AG, Hamburg, Fed. Rep. of Germany. A mixture of unsatisfactory fragments of tobacco ribs and shreds of tobacco leaf laminae and/or tobacco ribs which are bonded to each other and/or are clumped together and/or crimped is treated to loosen the coherent and/or clumped shreds and/or uncrimp individual shreds and to thereupon separate the fragments of ribs from the thus liberated and/or straightened shreds. The treatment involves heating the mixture with steam, thereafter cooling (if necessary) the mixture, and thereupon pneumatically, separating the shreds from the fragments of tobacco ribs. The heating operation can take place simultaneously with moisturizing of the mixture and can be carried out in a rotary or vibratory conveyor.