Though it is nominally a region of Burgundy there are several factors that make Chablis a quite distinct wine style from its southerly neighbours. The first is distance, the vineyards here being more than sixty miles north of Beaune and separated from the rest of Burgundy by the Morvan Hills. The second is the soil which defines the amphitheatre of hills upon which the best sites lie. The Kimmeridgian clay, which the French call argilo-calcaire, is packed with marine fossils, which in this area sits atop limestone. Finally, and crucially, the climate is considered semi-continental, with no real maritime influence, and where winters are hard and very cold and summers generally hot. One of the biggest risks facing Chablis growers is frost which is a regular and damaging visitor. It is one of the key factors in determining how much wine will be made in any given vintage and most growers go to extraordinary lengths to protect their vines every spring, including heaters among the vines and ...
Chardonnay is the only permitted variety, though there are two schools of thought on how to treat it in the winemaking. Some seek the purest expression of the terroir and the fruit, emphasising the steely, mineral qualities, while others believe that a dash of oak after fermentation can add layers of flavour and complexity to the wine. Most producers eschew oak, and those that do use new barrels rarely use it without restraint.
As with the rest of Burgundy, a hierarchy exists to demarcate the best vineyards. Seven Grand Cru vineyards have been registered, all on the south-west facing slopes of the valley of the Serein river. Below this level are 40 Premiers Cru sites. The area that is permitted to produce Chablis AC and some Premiers Crus has expanded in recent decades, as frost damage has been contained, and this has caused some controversy despite arguments that the land newly planted was once Premiers Cru before phylloxera constricted the land under vine.
The local cooperative makes about a third of all Chablis, though more and more growers who were once committed to the co-op are now making wine for themselves, which has also led to a concomitant reduction in the number négociants.