Baumé). After crushing, the must usually undergoes a period of extended maceration that can last up to 30 days. During this time the cap of grapes skins is frequently punched down (pigeage) or the juice pulled out from under the tank and pumped over the cap to allow for a more thorough extraction of phenolics that influence tannin, colour and aroma. Usually during this maceration, the fermentation process starts with ambient yeasts in the cellar. Often the wine will have fermented to the point where the grape spirits are added before maceration has ended and the wine is pressed off the skins, a process known as mutage sur grains. The added alcohol during maceration allows for more ethanol-soluble phenolics and flavor compounds to be extracted. After pressing, the wine is left to settle in concrete vats over the winter before it is racked into barrels or other containers. Since the fermentation process is halted rather quickly, the flavors of Maury do retain some of the natural primary grape aromas of Grenache along with some of the early fermentation esters that develop. But most of the distinctive character of Maury come from the aging process that can take place in a wide range of containers (from concrete and oak barrels to glass bonbonnes) kept in a variety of conditions (including out in the sun for deliberate oxidation) for a number of years depending the particular house style of the winemaker. Rancio One style of Maury known as rancio is produced when the wine is racked into clear glass demi-johns or bonbonne and left out in the summer sun to oxidize and age. This causes many of the colour compounds and tannins in the wines to fall out, leaving a thick, dark coloured deposit in the bonbonne. This deposit is allowed to stay in the bonbonne to influence the colour and flavour of resulting vintages of wine that are aged in the container. Once the wine has finished aging for the summer it is usually blended with wine that has spent time aging in large foudres oak cask or sold separately as Maury Rancio. Comparison to Port While the Portuguese wine Port is similarly made with a mutage halting the fermentation, there are some distinct differences in how vin doux naturels like Maurys are made. For one, the fortifying spirits used in Port are of a lower alcohol strength (traditionally 77%) while