Editing Sparkling wine (section)

==Production==
{{Main|Sparkling wine production}}
[[File:Harvesting Chardonnay grapes.jpg|upright|thumb|While harvesting grapes destined for sparkling wine, premium producers will take extra care to handle the grapes as gently as possible in order to minimize the extraction of harsh phenolic compounds from the skin.]]

The [[viticultural]] and [[winemaking]] practices of making sparkling wine have many similarities to the production of still wine with some noted divergence.<ref name="winefolly/sparkling-made">{{cite web |title=How Sparkling Wine is Made |url=https://winefolly.com/deep-dive/how-sparkling-wine-is-made/ |website=Wine Folly |access-date=7 March 2023}}</ref> At the vineyard, grapes are [[harvested (wine)|harvested]] early when there is still high [[acid levels (wine)|acid levels]]. In areas like Australia, winemakers aim to harvest the grapes at 17 to 20° [[brix]] (the sugar content of a solution). Unlike still wine production, high [[sugar levels (wine)|sugar levels]] are not ideal and grapes destined for sparkling wine production may be harvested at higher [[yields (wine)|yields]]. Care is taken to avoid tannins and other [[phenolic compounds (wine)|phenolic compounds]] with many premium producers still choosing to harvest by hand rather than risk mechanical harvesting which may split the berries and encourage [[maceration (wine)|maceration]] between the skins and juice. The press house is often close by the vineyard to where the grapes can be quickly [[pressed (wine)|pressed]] and separated from their skins. Red wine grapes like [[Pinot noir]] can be used in the production of white sparkling wines because their juice is initially clear and is only later [[color (wine)|tinted red]] through exposure to the color pigments in grape skins. While some skin exposure may be desirable in the production of [[rosé]] sparkling wines and some ''blanc de noirs'' (white of blacks), most sparkling wine producers take extended precautions to limit the amount of skin contact.<ref name="Oxford pp 656-660"/>

The primary [[fermentation (wine)|fermentation]] of sparkling wine begins like most other wines, though winemakers may choose to use specially cultivated sparkling wine [[yeast]]s. The wines may go through [[malolactic fermentation]], though producers wishing to make fruitier, simpler wines will usually forgo this step. After fermentation the base wines are then blended to form a ''[[cuvée]]''. While there are examples of [[varietal]] sparkling wines, such as ''blanc de blancs'' (white of whites) made from 100% [[Chardonnay]], most sparkling wines are blends of several grape varieties, vineyards and [[vintage]]s. Producers with wide access to grapes will use wines from several hundred base wines to create a blend that reflect the "house style" of their non-vintage wine. It is through the initiation of a [[Secondary fermentation (wine)|secondary fermentation]] that distinguishes sparkling wine production and gives the wine its characteristic bubbles. One of the by-products of fermentation is the creation of carbon dioxide gas. While this is able to be released during the first fermentation, efforts are taken during the second fermentation to retain the gas and have it dissolve into the wine. This creates high pressure within the wine bottle (on average around 5 [[Atmosphere (unit)|atmospheres]]) and wine producers take care to package the wine in strong glass bottles. When the wine is opened and poured into a glass, the gas is released and the wine becomes sparkling.<ref name="Oxford pp 656-660"/>

===Secondary fermentation===
[[File:Moet and glass.jpg|left|thumb|upright|The [[Sparkling wine production#transfer method|transfer method]] is used to make small and large format bottles of sparkling wine, such as this split (quarter bottle) of champagne.]]
There are several methods used to carry out this secondary fermentation. The most well known is the ''[[Traditional method|traditional]]'' or ''"champagne method"'' where the base ''cuvée'' is bottled with a mixture of sugar and yeast. The introduction of a fresh yeast and food source (the sugar) triggers the fermentation process in the bottle that the wine will eventually be sold in. Through the process of [[riddling]] and eventually [[Disgorging|disgorgement]], the dead yeast cells (called [[lees (wine)|lees]]) are removed from the wine while still maintaining the dissolved carbon dioxide gas. A [[sparkling wine production|dosage]] mixture of fresh wine and some sugar syrup is used to adjust the sweetness level of the wine after it has been disgorged.{{citation needed|date=October 2024}}

In the ''[[Sparkling wine production#ancestral method|methode ancestrale]]'' (ancestral method), the disgorgement step is skipped and the wine is sold with the lees still present as sediment in the wine. In the [[Sparkling wine production#transfer method|transfer method]], after the wines have gone through the traditional method including riddling and disgorgement, the bottles are emptied into a large tank where they are then transferred to small and large format [[wine bottle]]s such as 3 litre ''jeroboam'' and small split sizes used on airlines.<ref name="Oxford pp 656-660"/> Numerous quality producers worldwide use the "Traditional" method to make their sparkling wines.{{citation needed|date=October 2024}}

The ''[[Sparkling wine production#charmat method|Charmat method]]'' takes place in stainless steel fermentation tanks that are pressurized. The fresh yeast and sugar mixture is added to the wine which rapidly stimulates fermentation in the pressurized environment. The wine is then cooled, [[clarified (wine)|clarified]], and bottled using a counter pressure filler. The process of carbon injection (or carbonation), the method used to make [[soda pop]] fizzy, does not involve initiating a secondary fermentation but rather injecting carbon dioxide gas directly into the wine. This method produces large bubbles that quickly dissipate and is generally only used in the cheapest sparkling wines.<ref name="Oxford pp 656-660"/>

===Bubbles===
{{see also|Carbonation}}
[[File:Rose champagne infinite bubbles.jpg|left|thumb|upright|Bubbles in a rosé sparkling wine]]
An initial burst of effervescence occurs when the sparkling wine contacts the dry glass on pouring. These bubbles form on imperfections in the glass that facilitate [[nucleation]].
Nucleations are needed to stimulate the formation of bubbles because carbon dioxide has first to diffuse from the wine solution before it can rise out of the glass and into the air. A poured glass of sparkling wine will lose its bubbliness and carbon dioxide gas much more quickly than an open bottle alone would.<ref name="Oxford pp 272-273">J. Robinson (ed.) ''The Oxford Companion to Wine'' (third ed.), pp. 272–273. Oxford University Press 2006 {{ISBN|0-19-860990-6}}.</ref> The [[frothiness]] or "mousse" of the wine, along with the average size and consistency of the bubbles, can vary depending on the quality of the wine and the type of glass used.<ref name="Oxford pp 656-660"/>

[[File:Champagne bubbles mousse.jpg|right|thumb|As the bubbles rise to the surface of the glass, they form a frothy ''mousse''.]]
According to the wine academic Graham Harding, the average bottle of champagne contains enough carbon dioxide to potentially produce 49 million bubbles.<ref name="Miscellany">G. Harding (2005). ''A Wine Miscellany'', pp. 136–137. New York: Clarkson Potter Publishing. {{ISBN|0-307-34635-8}}.</ref> Wine expert [[Tom Stevenson]] puts the number at 250 million.<ref name="Stevenson pp 169-178"/> The bubbles initially form at 20 [[micrometre|micrometer]]s in diameter and expand as they gain buoyancy and rise to the surface. When they reach the surface they are approximately 1 millimeter in size. It is speculated that the bubbles in sparkling wine may speed up [[alcohol intoxication]] by helping the alcohol to reach the bloodstream faster. A study conducted at the [[University of Surrey]] in the United Kingdom gave subjects equal amounts of flat and sparkling champagne which contained the same [[alcohol level|levels of alcohol]]. After 5 minutes following consumption, the group that had the sparkling wine had 54 milligrams of alcohol in their blood while the group that had the same sparkling wine, only flat, had 39 milligrams.<ref name="Miscellany"/>

Putting a spoon in an open bottle of sparkling wine to keep it bubbly is a myth. A proper stopper is much more effective.<ref>{{Cite web |url=https://www.theguardian.com/food/2021/dec/31/putting-spoon-in-open-bottle-champagne-sparkling-wine-does-not-keep-it-bubbly |title=No, putting a spoon in an open bottle of champagne doesn't keep it bubbly – but there is a better way &#124; Geoff Scollary for The Conversation |first=Geoff Scollary for The |last=Conversation |date=31 December 2021 |website=The Guardian}}</ref><ref>{{Cite web |url=https://www.decanter.com/learn/advice/putting-spoon-in-champagne-work-ask-decanter-349914/ |title=Does putting a spoon in Champagne work? |first=Ellie |last=Douglas |date=13 December 2016 |website=Decanter}}</ref>

===Sweetness===
{{further|Sweetness of wine#Terms used to indicate sweetness of sparkling wine|History of Champagne#From sweet to brut}}
<!-- This section is linked to from numerous redirects, including [[Extra sec]], [[Extra Dry]], [[Brut zero]], etc. If you change this section name, please update all inbound redirects -->
The amount of sugar (dosage) added after the second fermentation and aging varies and will dictate the sweetness level of the sparkling wine. Wines produced within the European Union must include the sweetness level on the [[wine label]]. For wines produced outside the EU, the sweetness level is not required but if it is included on the label the terms used must conform to EU guidelines.<ref name="Stevenson pp 169-178"/>

[[File:French champagne nm.jpg|upright|thumb|A French champagne designated as "Extra Dry"]]
* ''Brut Natural'' or ''Brut Zéro'' (fewer than 3&nbsp;grams of sugar per litre)
* ''Extra Brut'' (fewer than 6&nbsp;grams of sugar per litre)
* ''Brut'' (fewer than 12&nbsp;grams of sugar per litre)