The invention relates to a method for treating pourable products consisting of particles which can be separated, especially seeds (2), with ultraviolet radiation (14). Said method consists of guiding a transparent product flow in a product guiding channel (1) through the radiation field, generated by at least one UV source (12), under low pressure or excess pressure, and using the force of gravity. The product flow is guided by means of an accelerated gas flow (5) in such a manner that its movement corresponds in terms of amount and direction to the accelerated movement of the particles falling in said product flow due to gravitational acceleration. The invention also relates to a device which accelerates the gas flow (5) in the required manner due to the formation of the product guiding channel (1).
