Abstract: A method of portioning a material and a portioning machine for carrying out the method, the portioning machine comprising a body having an inlet and outlet with gate means movable within the body to selectively open the inlet and the outlet and piston means for compacting material in said body to a predetermined density and for extruding a predetermined quantity of material from the outlet. The piston may be provided with pressure sensitive means which are adjustable so that the density of material compacted can be preselected.