Oechsle scale The mass difference between equivalent volumes of must and water is almost entirely due to the dissolved sugar in the must. Since the alcohol in wine is produced by fermentation of the sugar, the Oechsle scale is used to predict the maximal possible alcohol content of the finished wine. This measure is commonly used to select when to harvest grapes. In the vineyard, the must density is usually measured by using a refractometer by crushing a few grapes between the fingers and letting the must drip onto the glass prism of the refractometer. In countries using the Oechsle scale, the
History of the wine press their wine. By at least the 18th dynasty, the ancient Egyptians were employing a "sack press" made of cloth that was squeezed with the aid of a giant tourniquet. The use of a wine press in winemaking is mentioned frequently in the Bible but these presses were more elaboration of treading lagars where grapes that were tread by feet with the juice running off into special basins. The more modern idea of a piece of a winemaking equipment used to extract the juice from the skins probably emerged during the Greco-Roman periods where written accounts by Cato the Elder, Marcus