The principle of coffee siphon preparation is based on the use of vacuum. In A glass vessel is used to heat water. By the steam of boiling water becomes the water is forced through a thin glass tube into an upper vessel. In this unites itself fresh coffee with the rising water. When the heating is stopped, it will come on Underpressure and the water is sucked again into the lower vessel. The coffee particles are filtered out. The coffee can now be decanted and is for tasting ready. The water only comes in contact with glass, which indicates the purity of the product Coffee taste provides.