Tobacco conditioning apparatus comprising a covered generally U-shaped trough (2) containing an axially extending rotatable paddle assembly (8, 16). Tobacco to be conditioned is introduced through an aperture (6) in the cover (4) at the inlet end, and the trough is mounted with its axis inclined downwardly towards the outlet end so that the tobacco is progressively moved from the inlet to the outlet by rotation of the paddle assembly, while being conditioned with a steam spray. The tobacco leaves the outlet end through an aperture (7) in the base of the trough.