A bag containing bicarbonate powder, the bag (1) lacking any kind of dip tube and/or filter, being divided into two pockets (2, 3), which are arranged one next to the other and contain bicarbonate powder (B), and having a lower U-shaped channel (5), which establishes a communication between said bottom portions (6, 7) and has a central section (8) that is arranged under the minimum level of both bottom portions (6, 7), so that the lower channel (5), in use, is normally full of bicarbonate powder.
