<p>Fluidic material is fed into a product portioning chamber (66) forcing a piston (62) from a first position to a second position. The piston is then driven by a pneumatic fluid back to the first position so as to deliver the portioned fluidic material from the product portioning chamber through an outlet (18). A storage chamber (86) for the pneumatic fluid is provided so that pneumatic fluid is transferred from the compression chamber (70) back to the storage chamber to conserve the fluid when the piston is forced from the first position to the second position.</p>
