A volumetric displacement preservation system (10, 100) for preserving a volume of flowable substance in an open inner volume of a vessel, whereby the volumetric displacement preservation system (10, 100) comprises: a fluid exchange structure with a stopper (16, 102) for creating a sealing engagement with the vessel; a fluid exhaust pathway (24, 104) in the fluid exchange structure with a first end to be in fluidic communication with the open inner volume of the vessel and a second end to be in fluidic communication exterior to the vessel if the stopper (16, 102) is engaged with the vessel, wherein the fluid exhaust pathway (24, 104) has an open condition where fluid can pass through the fluid exhaust pathway (24, 104) and a closed condition where fluid substantially cannot pass through the fluid exhaust pathway (24, 104); a fluid inlet pathway (26, 106) in the fluid exchange structure separate from the fluid exhaust pathway (24, 104) with a first end to be in direct fluidic communication with the open inner volume of the vessel and a second end to be in fluidic communication exterior to the vessel when the stopper (16, 102) is engaged with the vessel wherein the fluid inlet pathway (26, 106) has an open condition where fluid can pass through the fluid inlet pathway (26, 106) and a closed condition where fluid substantially cannot pass through the fluid inlet pathway (26, 106); characterized in that a chamber (14, 110) comprising an expandable and compressible bladder with an inner volume for retaining a volume of preservative gas and an orifice for dispensing the preservative gas from the chamber (14, 110); and a fluidic connection for fluidically connecting the orifice of the chamber (14, 110) to the second end of the fluid inlet pathway (26, 106) so that the chamber (14, 110) is retained externally to the open inner volume of the vessel; whereby, if the fluid exhaust pathway (24, 104) and the fluid inlet pathway (26, 106) are in closed conditions, fluid cannot be exhausted through the fluid exhaust pathway (24, 104) and fluid cannot be received through the fluid inlet pathway (26, 106) and whereby, if the fluid exhaust pathway (24, 104) and the fluid inlet pathway (26, 106) are in open positions, liquid can be dispensed from the open inner volume of the vessel through the fluid exhaust pathway (24, 104) under the force of gravity and preservative gas can be drawn from the open inner volume of the expandable and compressible bladder of the chamber (14, 110) and into the open inner volume of the vessel through the fluid inlet pathway (26, 106) in volumetric displacement of the liquid exhausted through the fluid exhaust pathway (24, 104) whereby the expandable and compressible bladder of the chamber (14, 110) can progressively deflate as liquid is dispensed from the open inner volume of the vessel. a fluid exchange structure with a stopper (16, 102) for creating a sealing engagement with the vessel; a fluid exhaust pathway (24, 104) in the fluid exchange structure with a first end to be in fluidic communication with the open inner volume of the vessel and a second end to be in fluidic communication exterior to the vessel if the stopper (16, 102) is engaged with the vessel, wherein the fluid exhaust pathway (24, 104) has an open condition where fluid can pass through the fluid exhaust pathway (24, 104) and a closed condition where fluid substantially cannot pass through the fluid exhaust pathway (24, 104); a fluid inlet pathway (26, 106) in the fluid exchange structure separate from the fluid exhaust pathway (24, 104) with a first end to be in direct fluidic communication with the open inner volume of the vessel and a second end to be in fluidic communication exterior to the vessel when the stopper (16, 102) is engaged with the vessel wherein the fluid inlet pathway (26, 106) has an open condition where fluid can pass through the fluid inlet pathway (26, 106) and a closed condition where fluid substantially cannot pass through the fluid inlet pathway (26, 106); characterized in that a chamber (14, 110) comprising an expandable and compressible bladder with an inner volume for retaining a volume of preservative gas and an orifice for dispensing the preservative gas from the chamber (14, 110); and a fluidic connection for fluidically connecting the orifice of the chamber (14, 110) to the second end of the fluid inlet pathway (26, 106) so that the chamber (14, 110) is retained externally to the open inner volume of the vessel; whereby, if the fluid exhaust pathway (24, 104) and the fluid inlet pathway (26, 106) are in closed conditions, fluid cannot be exhausted through the fluid exhaust pathway (24, 104) and fluid cannot be received through the fluid inlet pathway (26, 106) and whereby, if the fluid exhaust pathway (24, 104) and the fluid inlet pathway (26, 106) are in open positions, liquid can be dispensed from the open inner volume of the vessel through the fluid exhaust pathway (24, 104) under the force of gravity and preservative gas can be drawn from the open inner volume of the expandable and compressible bladder of the chamber (14, 110) and into the open inner volume of the vessel through the fluid inlet pathway (26, 106) in volumetric displacement of the liquid exhausted through the fluid exhaust pathway (24, 104) whereby the expandable and compressible bladder of the chamber (14, 110) can progressively deflate as liquid is dispensed from the open inner volume of the vessel.