the present invention resides in a beverage making machine containing a purification unit for purifying potable water . the purifying unit contains a purifying agent and is detachably mounted on either the water reservoir or on the basket where water contacts the brewing agent or beverage making agent of the beverage machine . in an alternate mode , the water purifying unit is located below the water reservoir of a beverage making machine . the bottom member of the water purifying unit is detachably mounted on the bottom of said units with screw - on means .