Sauternes is a sweet wine made with specially prepared grapes from the region of Sauternais, which is located in the Graves section of Bordeaux France. What makes this type of wine unique is the use of grapes which have been exposed to a fungus called noble rot. The fungal rotting causes a heightened sweetness which makes Sauternes a popular French dessert wine. Types of noble-rotted grapes used in Sauternes include Sauvignon Blanc, Semillon, and Muscadelle grapes.
The balanced sweetness and acidity of this dessert wine complements the strong flavor of aged cheeses such as Roquefort and Muenster. Noble rot wines are commonly served chilled to around 53 degrees Fahrenheit (11 degrees Celsius) with well-aged vintages poured at a slightly warmer temperature. Like most French dessert wines, Sauternes is often sold in 375 milliliter bottles, which are half the size of a traditional 750 milliliter wine bottle. Personal serving sizes are also smaller than many wines at around 2 to 3 fluid ounces (59 to 88 milliliters) per wine glass.
Weather conditions from year to year greatly effect the character of each vintage. The percentages of Sauvignon Blanc, Semillon, and Muscadelle grapes are adjusted for each production to provide optimum balance and rich flavor. Some high-quality Sauternes are aged for as long as 100 years to intensify their flavor diversity and increase viscosity.
The warm and moist climate of Sauternais makes the grape vines especially susceptible to a fungal infection called botrytis cinerea. Many of the vineyards in the region are located in an area between two rivers where air masses of contrasting temperatures collide. During the warm summer months, these weather conditions have a tendency to create a layer of moisture that falls onto the vines when the sun goes down. This coating of mist provides ample moisture for the fungal growth until the water is evaporated in the afternoon heat. Sauternes producers often mimic these conditions when they do not naturally occur by lightly misting their vines in the cool of the evening.
Sauterne wine is different than true Sauternes. The term Sauterne wine refers to a large variety of white wines produced in California. California produced Sauterne wines are often sweet dessert wines made from white wine grapes that have never been exposed to noble rot fungus. Sauterne wine is often much less expensive than real French Sauternes, but usually has a decreased acid component and less of a balanced flavor.