Pack (100) having an inner volume in which a beverage medium is stored and from which an infusion beverage is prepared when a fluid is introduced inside the pack (100), said inner volume being defined by sheets of material joined to one another at their edges, such that the inner volume presents a generally plane shape, said pack (100) comprising an inlet chamber (120) configured to accommodate an inflow of fluid that will infuse the beverage medium to produce an infusion beverage and at least one outlet duct (12) for delivering the infusion beverage from said inner volume, said inlet chamber (120) and said outlet duct (12) being positioned at the bottom of the pack (100), the pack (100) further comprising a compartmental channel (250) and a filtering element (30) configured in such a way that they define a dedicated chamber inside the volume of the pack where the beverage medium is confined, the filtering element (30) being further configured for preventing the particles of the beverage medium from entering the outlet duct (12) when fluid is introduced in the pack and the infusion beverage is prepared, thus preventing these particles from being delivered together with the infusion beverage.