A device for accurately metering food. The device includes an outer part
and an inner metering part having a dosing chamber and a piston block
slideably mounted therein. The housing outer part has three passageways,
and the dosing chamber is configured, dimensioned, and positioned to
alternately connect two of the three passageways of the outer part. The
inner metering part is configured, dimensioned and positioned for
rotation within the outer part. The outer housing part and the inner
metering part are mounted concentrically with the inner metering part and
the inner metering part has only one degree of liberty in rotation around
a central axis of rotation.