Addition of sugar in various forms to fresh grapes, grape must, partially fermented grape must, young wine (not yet fully fermented) and wine. The terms alcohol enhancement, improvement, chaptalisation or vintage enhancement are also used for this. 17 to 19 grams of sugar per litre of wine increase the alcohol content by about 1% vol. However, the process has nothing to do with sweetening a wine (increasing the residual sugar) or spriting (adding alcohol to the finished wine). The aim is to increase the natural alcohol content in the wine by fermenting the additional sugar.