GB912326A - Improvements in or relating to extracting a constituent extractable by a liquid in the cold from a material containing same - Google Patents

Abstract

912,326. Coffee and like extracts. KOELLE, G., and KOELLE, S. Dec. 28, 1959, No. 43964/59. Class 129. Coffee or other material is extracted by circulating the extracting liquid under reduced pressure in a closed circuit, withdrawing a small amount of the liquid from the circuit and using it for cold extraction of the material under reduced pressure and feeding the product back into the circuit; a second extraction with the same or a different liquid, and preferably at a more reduced pressure, can be carried out. The vacuum conduit 12 draws cold water from a container 2 through a steam-heated section to a collector 6 whence the liquid can return to the container. Vapour is withdrawn from the collector through a pipe 9 and past a cooling coil 10 where it condenses and falls on the material to be extracted in the vessel 13, where it collects until it siphons over the tube 16 back to the container 2. The material can be further extracted with the same or a different liquid and under more reduced pressure. The extract is fed to a container 20 containing a stirring mechanism, and other materials such as fructose can be added. From the container 20, the extract passes to a drier 23 and storage receptacle 24. The extracted material in the vessel 13 is dried in a drier 25 and ground in a mill 27, after which it can be added to the extract in the container 20. A simpler form of apparatus is also described.