The apparatus is constituted by at least an operating unit comprising: a chute, inferiorly associated to a hopper for containing granular or powder product, the chute being extended downwards to convey the product towards an underlying container; a rotary obturator having a horizontal axis X, for transversally occluding the chute and being laterally provided with an opening destined to place the chute in communication with a batching chamber, realized internally of the body of the obturator and delimited, on an opposite side to the opening, by a gas-permeable wall; a conduit connected at an end thereof to the batching chamber, via the wall, and at another end thereof to aspirating and blowing means; motorized organs for commanding rotations of the obturator, with which the opening is alternatingly oriented upwards, during the loading stage, in order to enable the granular or powder products, falling from the hopper and introduced into the upper part of the chute to enter the batching chamber, which is depressed thanks to the action of the aspirating means, and in a downwards direction, during the subsequent delivery stage, to enable the batched volume of granular or powder product, projected by a jet of pressurized gas generated by the blowing means, to exit the batching chamber and enter the lower part of the chute to descend towards the container.