View source for Secondary fermentation (wine)

[[File:Mthomebrew maceration.JPG|right|thumb|400px|In red wine production, the [[maceration (wine)|maceration]] process was traditionally done in large vats where the [[fermentation (wine)|fermentation]] process would begin ''(in the picture this is noted by the presence of carbon dioxide bubbles)''. Secondary fermentation would take place when the wine is transferred to a second container such as a carboy or oak barrel.]]

'''Secondary fermentation''' is a process commonly associated with [[winemaking]],<ref name="Oxford pg 618">J. Robinson (ed) ''"The Oxford Companion to Wine"'' Third Edition pg 618 Oxford University Press 2006 {{ISBN|0-19-860990-6}}</ref> which entails a second period of [[Ethanol fermentation|fermentation]] in a different vessel than the one used to start the fermentation process. An example of this would be starting fermentation in a [[carboy]] or stainless steel tank and then moving it over to [[oak barrels]]. Rather than being a separate, second fermentation, this is most often one single fermentation period that is conducted in multiple vessels. However, the term does also apply to procedures that could be described as a second and distinct fermentation period.<ref name="Oxford pg 618"/>

==In wine production==
[[File:Undegorgierter Champagner.jpg|left|thumb|200px|With [[sparkling wine]]s, the by product of secondary fermentation is the containment of the carbon dioxide bubbles which makes the wine "sparkling" as well as dead [[yeast (wine)|yeast]] cells known as [[lees (fermentation)|lees]] ''(visible in the picture)'' that must be removed in a process known as ''disgorgement'' that happens prior to corking.]]

In [[sparkling wine production]], the secondary fermentation often takes places in the wine bottle that the wine will be sold in. This is most commonly known as the ''méthode champenoise'' or "[[Champagne (wine)|Champagne]] method" after the [[Champagne (wine region)|region]] most noted for sparkling wine production. When the base wine (or ''[[cuvee]]'') has been produced from single [[grape (variety)|grape]] [[varietal]]s or a blend, the wine is bottled with a mixture of yeast and fresh sugar known as the ''"liqueur de tirage"''. This secondary fermentation, also known as bottle fermentation, is the process that makes the wine "bubbly" due to the containment of [[carbon dioxide]] which is normally released as a by product in regular fermentation. 

In still wine production, particularly of red wines<ref>{{Cite web |title=Red Wine |url=https://bottlebarn.com/collections/red-wine |website=Bottle Barn}}</ref> and some white wines like [[Chardonnay]], the secondary fermentation process can also usher in the use of [[malolactic fermentation]] (or MLF) where the hard, green apple-like [[malic acid]] is converted into softer, butter-like [[lactic acid]]. In the case of a [[stuck fermentation]], a winemaker may wish to transfer the [[must]] to a second vessel and use stronger, more aggressive yeasts with high fermentation temperatures to re-initiate the fermentation process. A similar process known as ''[[governo]]'' has been used by [[Tuscany (wine)|Tuscan winemaker]]s since the 14th century with the isolation after [[harvest (wine)|harvest]] of a batch of grapes that can be added later to the wine to help prevent (or recover from) a stuck fermentation.<ref name="Oxford pg 618"/>
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==See also==
*[[Glossary of wine terms]]

==References==
{{reflist}}

==Further reading==
* American Journal of Enology and Viticulture ''"[http://www.ajevonline.org/cgi/content/abstract/44/1/93 Studies on the Secondary Fermentation of Low-Alcohol Sparkling Apple Wine]"'' 44:1:93-98 (1993)
*Jeff Cox ''"From Vines to Wines: The Complete Guide to Growing Grapes and Making Your Own Wine"'' Storey Publishing 1999 {{ISBN|1-58017-105-2}}
* SQ Liu  ''"[https://doi.org/10.1046/j.1365-2672.2002.01589.x Malolactic fermentation in wine - beyond deacidification]"'' - Journal of Applied Microbiology, 2002 Volume 92 Issue 4 Page 589-601
*William Patton ''"The laws of fermentation and the wines of the ancients"'' University of Michigan Publishing 2005 {{ISBN|1-4255-0928-2}}

==External links==
* Winemaking basics ''"[http://winemaking.jackkeller.net/secondary.asp Transfer to secondary]"''

{{Wines}}

[[Category:Winemaking]]
[[Category:Wine terminology|*]]