Chardonnay is a green-skinned grape variety used in the production of white wine. The variety originated in the Burgundy wine region of eastern France, but is now grown wherever wine is produced, from England to New Zealand. For new and developing wine regions, growing Chardonnay is seen as a ‘rite of passage’ and an easy entry into the international wine market.

The Chardonnay grape itself is neutral, with many of the flavours commonly associated with the wine being derived from such influences as terroir and oak. It is vinified in many different styles, from the lean, crisply mineral wines of Chablis, France, to New World wines with oak and tropical fruit flavours. In cool climates (such as Chablis and the Carneros AVA of California), Chardonnay wine tends to be medium to light body with noticeable acidity and flavours of green plum, apple, and pear. In warmer locations (such as the Adelaide Hills and Mornington Peninsula in Australia and Gisborne and Marlborough region of New Zealand), the flavours become more citrus, peach, and melon, while in very warm locations (such as the Central Coast AVA of California), more fig and tropical fruit notes such as banana and mango come out. Wines that have gone through malolactic fermentation tend to have softer acidity and fruit flavours with buttery mouthfeel and hazelnut notes.

Chardonnay is an important component of many sparkling wines around the world, including Champagne and Franciacorta in Italy.

Chardonnay's popularity peaked in the late 1980s, then gave way to a backlash among those wine connoisseurs who saw the grape as a leading negative component of the globalisation of wine. Nonetheless, it is one of the most widely planted grape varieties, with 210,000 hectares (520,000 acres) worldwide, second only to Airén among white wine grapes and fifth among all wine grapes.

Chardonnay lends itself to almost any style of wine making from dry still wines, to sparkling wines to sweet late harvest and even botrytized wines (though its susceptibility to other less favourable rot makes these wines rarer). The two winemaking decisions that most widely affect the end result of a Chardonnay wine is whether or not to use malolactic fermentation and the degree of oak influence used for the wine. With malolactic fermentation (or MLF), the harder malic acid gets converted into the softer lactic acid, and diacetyl which creates the "buttery-ness" that is associated with some styles of Chardonnay. The wines that do not go through MLF will have more green (unripe) apple like flavours. Oak can be introduced during fermentation or after in the form of the barrel aging. Depending on the amount of charring that the oak was treated with, this can introduce a "toastiness" and flavours that many wine drinkers mistake as a characteristic of the grape itself. These flavours can include caramel, cream, smoke, spice, coconut, cinnamon, cloves and vanilla.

Other winemaking decisions that can have a significant effect include the temperature of fermentation and what time, if any, that the wine allowed to spend aging on the lees. Burgundian winemaking tends to favour extended contact on the lees and even "stirring up" the lees within the wine while it is aging in the barrel in a process known as bâttonage. Colder fermentation temperatures produces more "tropical" fruit flavours like mango and pineapple. The "Old World" style of winemaking favours the use of wild, or ambient yeast, though some will also use specially cultivated yeast that can impart aromatic qualities to the wine. A particular style of yeast used in Champagne is the Prise de Mousse that is cultivated for use worldwide in sparkling Chardonnay wines. A potential drawback of using wild yeast is that the fermentation process can go very slow with the results of the yeasts being very unpredictable and producing potentially a very different wine each year. One Burgundian winemaker that favours the use of only wild yeast is Domaine des Comtes Lafon which had the fermentation of its 1963 Chardonnay batch take 5 years to complete when the fermentation process normally only takes a matter of weeks.

The time of harvesting is a crucial decision because the grape quickly begins to lose acidity as it ripens. For sparkling wine production, the grapes will be harvested early and slightly unripe to maintain the acid levels. Sparkling Chardonnay based wines tend to exhibit more floral and steely flavours in their youth. As the wine ages, particularly if it spends significant time on lees, the wines will develop "toasty" notes. Chardonnay grapes usually have little trouble developing sugar content, even in cooler climates, which translates into high potential alcohol levels and limits the need for chaptalisation. On the flip side, low acid levels can be a concern which make the wine taste "flabby" and dull. Winemakers can counteract this by adding tartaric acid in a process known as "acidification". In cooler climates, the extract and acidity of Chardonnay is magnified which has the potential of producing very concentrated wines that can develop through bottle aging. Chardonnay can blend well with other grapes and still maintain some of its unique character. The grapes most often blended with Chardonnay include Chenin Blanc, Colombard and Sémillon.

Due to the "malleability" of Chardonnay in winemaking and its ability to reflect its terroir, there is not one distinct universal "style" or set of constants that could be applied to Chardonnay made across the globe. According to Jancis Robinson, a sense of "smokiness" is one clue that could be picked up in a blind tasting of Chardonnay but there are many styles that do not have any "smoky" notes. Compared to other white wine grapes like Sauvignon Blanc, Gewürztraminer and Viognier-Chardonnay has a more subtle and muted nose with no overwhelming aromatics that jump out of the wine glass. The identifying styles of Chardonnay are regionally based. For example, pineapple notes are more commonly associated with Chardonnay from Napa Valley while Chablis will have more notes of green apples. While many examples of Chardonnay can benefit from a few years of bottle aging, especially if they have high acidity, most Chardonnays are meant to be consumed in their youth. A notable exception to this is the most premium examples of Chablis and white Burgundies.

Alternative Names: Morillon, Pinot Chardonnay, Feiner Weisser Burgunder