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
Straw wine scale. Grapes should originate in a single wine sub-region and reach at least 6% of alcohol. De Trafford created the first Vin de Paille to be released under the new appellation "Wine from Naturally Dried Grapes" in 1997. They use 100% Chenin blanc. A number of wineries produce straw wine, known in Spanish as "vino de pasas", including Bodegas Oliveros and Bodegas Gonzalez Palacios. Most involve a blend of two grapes, the first one usually a Muscat. Pedro Ximénez grapes are dried in the sun before being vinified, fortified and matured in a solera system like other sherries. Another straw