Personally, I appreciate things more when I understand them better, and it struck me this morning that, with the onset of my project’s first foray into sparkling wine, it might be helpful to explain a little bit about how Champagne and other sparkling wines are made.*
Wine, of course, is, at its core, fermented grape juice. As grape juice ferments, carbon dioxide forms. If the carbon dioxide is released, you have still wine. If, at some point, the wine maker prevents the carbon dioxide from escaping, you have sparkling wine. Simple, right? Okay, maybe not. There are actually three basic methods for making sparkling wine: (1) methode champenoise (the Champagne method); (2) the transfer method; and (3) the charmat (bulk) method.
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Again, all wine, including sparkling wine, starts the same way. Clear grape juice is obtained by pressing the grapes quickly yet gently, and the juice is fermented. Most sparkling wines are non-vintage, which means they are a blend of wines from different years. The reason for this is that it allows the winemaker to create a wine with the same characteristics and flavors as other years. Thus, when you buy a bottle of Dom, you know exactly what it will taste like. If you see/buy a sparkling wine of a particular vintage, you know that the wine maker believes that this vintage was a special year. After the blending, the methods start to diverge.
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Methode Champenoise This is definitely the most labor- and time-intensive method of making sparkling wine. After blending, a mixture of sugar and yeast (the liqueur de tirage) is added to the tank, and then the wine is bottled. The bottles are stored on their sides in a cool environment, and the liqueur de tirage causes a second fermentation. The carbon dioxide is trapped in the bottle, and the additional sugar is converted to alcohol. This process takes a couple of weeks, but the bottles remain stored on their side for much longer (anywhere from 12 months to 6 years). During this time, the spent yeast cells lie as sediment in the bottle and slowly break down. The breakdown of the yeast create amino acids and proteins that end up providing richer texture and flavor in the wine. Thus, the contact time between the yeast and wine plays a big role in the style and character of the ultimate product. The amount of time the wine spends in the bottle after the second fermentation also affects the size, consistency and persistence of the bubbles in the wine. The longer the wine rests, the more thoroughly the carbon dioxide becomes incorporated.
Once the wine has been appropriately aged, the bottles are moved to an A-frame wooden rack, with the neck of the bottles pointing downward at an angle. The yeast cells are maneuvered over time into the bottle’s neck and then onto the stopper in the mouth of the bottle. This process is called riddling (remuage) and was first developed by the wine makers at Veuve Clicquot. Depending on whether the riddling is done by hand or with a new, fancy schmancy machine, the riddling process usually takes 1 to 8 weeks.
After the riddling process is complete, the yeast cells are removed from the bottle through a process called disgorgement (degorgement). It used to be that this was done bottle by bottle by using a pair of pliers to remove the stopper, allowing a small amount of wine (and, presumably, the yeast) to escape. This system has obviously been improved over time and is now automated.
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Finally, while the stopper is off the bottle, most sparkling wine producers add a small amount of wine and liquid sugar – referred to as the final dosage – before inserting the cork. The amount of sugar added determines whether the final product is extra-brut (bone dry), brut (dry), extra dry (a little sweetness), sec (medium sweetness), demi-sec (sweet), or doux (very sweet). The bottles are then allowed to rest for 3 to 6 months before being released for sale.
Transfer Method Here, once the second fermentation is complete, the sparkling wine is transferred, under pressure, from the bottles into a tank, where it is filtered to eliminate the sediment. The dosage is added, and the wine is re-bottled. This is obviously a more expeditious method and, if done well, can produce good sparkling wine, especially if it is aged long enough.
Charmat (Bulk) Method Here, still wine is put in a pressurized tank, and sugar and yeast are added to create sparkling wine. The wine is filtered in bulk and then bottled. This method tends to produce delicate, fresh, and fruity sparkling wines such as Asti.
The point of this post is not to suggest that you should dismiss transfer or bulk method wines. On the contrary, it may very well be that you prefer the lighter sparkling wines produced by the bulk method, and there is absolutely nothing wrong with that. The goal of this post is to simply arm you with information that will help you understand what you’re drinking and why you like (or dislike) it so that you can make informed choices in the future. And, as a bonus, the next time someone tries to sell you on an expensive sparkling wine you’ve never heard of, you can ask informed questions that will help you determine whether the price tag is an accurate reflection of what you’re likely to find in the bottle.
Cheers!!
* In case you’re wondering, I learned about this stuff through a credential course offered by a company in Los Angeles called Learn About Wine. The course is called LAW (Learn About Wine) School and involves four intensive sessions followed by written and blind tasting exams. The textbook used for this course, Kolpan, Smith & Weiss, Exploring Wine (Second Ed.), is a great resource, and I often refer to it when researching which wines to buy for this blog.
** This photograph was taken from http://www.tescoma.es/en/katalog/xpoloz.php?skupina0=6&skupina=3&skupina2=1&polozka=695836
*** This handy dandy flow chart was taken from http://www.execellars.co.uk/images/SpkWineMaking.GIF
**** This photograph can be found at http://kimexco.com/Wine_Investments_Methode_Champenoise.html
