摘要 |
Extn. of soluble material out of cellular matter, which has been at least partially crushed, uses the action of pressing in the presence of a solvent liq. The cellular matter is only partly pressed in >=1 press stages and only expressed to a max. in the final stage. A solvent liquid is added to the last stage and this is passed counter-current down the previous pressing stages. This solvent can be water. The pressing operations can take place without the residue leaving the press. The solvent, the solution and/or the cellular matter can be heated and the temp. may be raised from one stage to the next. Cell opening enzymes may be added to the material, from the start or part way through. Esp. for use with agricultural extracts for food products. Simple expression of juices from fruit and vegetable material tends to leave a considerable amt. of useful material left on the residue, such as aromatic cpds., colour and sugar. The residues are generally used as animal feeds. By use of water, the amt. recovered can be greatly increased. However, the quantity of water needed means that the concn. is low. By the counter-current system this is much improved. |