Electrodialysis

electrodialysis, a sophisticated, electrically driven membrane filtration process which allows the removal of selected ions (electrically charged molecules), has been used since the 1960s to desalinate water and was adapted for use in the stabilization of wine by inra in the 1990s. In this context it is used to remove potassium, tartrates, and bitartrates. Despite the relatively high capital costs of the technology, it is gaining acceptance in the wine industry because it uses 80% less energy than cold stabilization, is much faster, and total running costs are up to 40% lower. The volume of water used to extract the tartrate salt has been significantly reduced by the use of reverse osmosis and there are said to be no adverse effects on wine quality. No further filtration is required to remove the potassium bitartrate crystals before bottling, although the wine does have to be filtered prior to electrodialysis to avoid clogging the membranes. One of the greatest advantages of this process is that it allows great control over what and how much is removed from the wine.