An eductor suitable for use in an assembly for preparing a liquid product, an assembly for preparing a liquid product and a system for preparing a liquid product

An eductor suitable for use in an assembly for preparing a liquid product comprises a housing having a substantially cylindrical wall. The eductor comprises an injector valve (13) which is displaceably arranged within the cylindrical wall from first position to a second position longitudinally spaced from the first position, and vice versa. On its outer surface the injector valve comprises two annular protrusions (16, 17) which are spaced from each other, each of the annular protrusions engaging the inner surface of the cylindrical wall (9) for forming a seal therewith, said annular protrusions together with the inner surface of the cylindrical wall forming an annular chamber, said protrusions being arranged for isolating the annular chamber from fluid communication with any environment outside the annular protrusions when said injector valve is positioned in the first position or the second position or any position in between. Alternatively or additionally the inner surface of the cylindrical wall comprises two annular protrusions which are spaced from each other by a distance that at least equals the distance between the first position and the second position of the injector valve. An assembly for preparing a liquid product comprises a holder containing a second liquid and such an eductor. A system for preparing a liquid product comprises a product preparation apparatus for preparing said liquid product and such an assembly.