Reverse osmosis

In wine, a technique by which alcohol levels are reduced. It's typically employed by winemakers who wish to achieve the flavor of ripe grapes without the increased percentage of alcohol that results from fruit with higher levels of sugar. The reverse osmosis process involves passing wine through a filter that separates water and ethanol from tannins and other elements responsible for pigment, flavor and aroma. The water and alcohol solution is then distilled to separate the two, with some of the alcohol being removed, and the remaining solution is added back to the other elements previously separated out.