Method for shaping, e.g. moulding, of three dimensional products from a mass of pumpable foodstuff material, for example from ground meat, wherein use is made of an installation comprising: - a hopper adapted to receive a batch of the mass of pumpable foodstuff material, - a positive displacement pump having an inlet and an outlet for the mass, the pump forming one or more pump chambers that each are successively in communication with the pump inlet for the introduction of mass into the one or more pump chambers and with the pump outlet for the discharge of mass from the one or more pump chambers, - a tube structure that is connected to the outlet of the positive displacement pump, said tube structure having at least one mouth from which said mass is discharged, said mass being shielded by said tube structure from the surrounding atmosphere, - a shaping device receiving mass from the at least one mouth of the tube structure, which shaping device shapes the mass into three dimensional products, e.g. a moulding device receiving the mass from the at least one mouth of the tube structure, said moulding device preferably comprising: - a frame, - a mould member having multiple mould cavities, each having a filling opening for the introduction of foodstuff material into the mould cavity, wherein the mould member is movably supported by the frame, - a mould member drive for moving the mould member along a path, said path including a fill position for filling the mass into a mould cavity and a product release position for releasing a moulded product from the mould cavity, - a mass feed member, preferably supported by the frame, having said mouth at the fill position along the path of the mould member, said mass feed member being connected to the fill tube and being adapted to transfer the mass into a mould cavity of the mould member when the filling opening thereof is in communication with the mouth at said fill position, wherein the installation comprises a controllable vacuum assembly adapted to cause controlled evacuation of air from the mass at one or more locations in the trajectory of the mass from the hopper to and including the pump chamber at a position where it is In communication with the pump inlet, characterized In that the level of evacuation provided by the vacuum assembly is used as a control mechanism to control the weight and/or porosity of the shaped, e.g. moulded, products. - a hopper adapted to receive a batch of the mass of pumpable foodstuff material, - a positive displacement pump having an inlet and an outlet for the mass, the pump forming one or more pump chambers that each are successively in communication with the pump inlet for the introduction of mass into the one or more pump chambers and with the pump outlet for the discharge of mass from the one or more pump chambers, - a tube structure that is connected to the outlet of the positive displacement pump, said tube structure having at least one mouth from which said mass is discharged, said mass being shielded by said tube structure from the surrounding atmosphere, - a shaping device receiving mass from the at least one mouth of the tube structure, which shaping device shapes the mass into three dimensional products, e.g. a moulding device receiving the mass from the at least one mouth of the tube structure, said moulding device preferably comprising: - a frame, - a mould member having multiple mould cavities, each having a filling opening for the introduction of foodstuff material into the mould cavity, wherein the mould member is movably supported by the frame, - a mould member drive for moving the mould member along a path, said path including a fill position for filling the mass into a mould cavity and a product release position for releasing a moulded product from the mould cavity, - a mass feed member, preferably supported by the frame, having said mouth at the fill position along the path of the mould member, said mass feed member being connected to the fill tube and being adapted to transfer the mass into a mould cavity of the mould member when the filling opening thereof is in communication with the mouth at said fill position, - a frame, - a mould member having multiple mould cavities, each having a filling opening for the introduction of foodstuff material into the mould cavity, wherein the mould member is movably supported by the frame, - a mould member drive for moving the mould member along a path, said path including a fill position for filling the mass into a mould cavity and a product release position for releasing a moulded product from the mould cavity, - a mass feed member, preferably supported by the frame, having said mouth at the fill position along the path of the mould member, said mass feed member being connected to the fill tube and being adapted to transfer the mass into a mould cavity of the mould member when the filling opening thereof is in communication with the mouth at said fill position,