Towards the end of the 20th century both grapes began to increase in popularity, particularly the Chardonnay vine which now accounts for nearly 45% of all Jura plantings and is valued for its good sugar levels and early ripening. Pinot noir is used to make a varietal style of wine or as a blend to deepen the color of the pale Poulsard grape. By itself, Poulsard makes a rosé in the Arbois-Pupillin region that is characterized by an orange "corail" tint. The Poulsard grape is also one of the primary grapes for the "vin de paille". The Trousseau grape performs best in the gravelly vineyards near Arbois that can give the grape the additional heat it needs to ripen into a deep colored, intensely flavored wine. The white Savagnin grape has some similarities with the possibly related Traminer and Gewürztraminer. While the grape is permitted in all styles of white Jura wine throughout the region it is mainly found in "vin jaune" where it proposes a nutty, full bodied wine that can age for an extended period of time. Savagnin, itself, is the only permitted variety for "vin jaune". Jura's most famous and distinguishable wine is the sherry-like "vin jaune". The wine is produced by picking the Savagnin as ripe as possible, in some cases becoming a sort of late harvest wine, and after fermentation storing it in Burgundian aging barrels for over 6 years. The barrels are filled up to the top and allowed to evaporate, reducing the volume in the barrel and a creating an air pocket at the top of the barrel. During this time the wine oxidizes and grows a film of yeast that is similar to, but not the same strain as, the Jerez region "flor". The wine is then bottled in a signature "clavelin" wine bottle that holds 62 cL. Vin jaune is an intensely flavored wine that often requires decanting prior to drinking. Due to the cool climate, chaptalization is permitted in the Jura region and is sometimes a necessity to compensate for the low sugar levels in the under ripe vintages. Most white wines in the region are aged in oak for several months prior to release while red wines are often aged in stainless steel tanks and bottled early. Producers in the Jura include Gaspard Feuillet, Chateau Béthanie, Domaine Berthet-Bondet, Frédéric Lornet and Henri Maire.