How do you make champagne?

To make champagne, manufacturers to start with develop a base wine, before including a mixture of yeast and sugar-- understood as the liqueur de tirage-- to it. The wine is then bottled, with the yeast and sugar setting off a second fermentation process inside the bottle. The sediment is then removed through a procedure known as riddling, prior to the bottles are topped up with a 'dose'-- a mixture of red wine and sugar-- and sealed with a champagne cork and wire cage.

The primary step in making champagne is to create a base red wine. To do this, producers source grapes from several of the Champagne region's many appellations d'origine contr�l�e (AOC).  https://geogenes.org/?p=323 The vast majority of champagne is made using a blend of 3 grapes: Pinot Noir, which gives the white wine body and structure; Pinot Meunier, which includes fruitiness; and Chardonnay, which imparts sophistication and skill.

When the grapes have been harvested-- typically by hand-- they are crushed and the juice (known as must) is extracted. The must is then moved to stainless-steel tanks, where it goes through a main fermentation. During this process, the yeast Aureobasidium takes in the grape sugar and produces alcohol and carbon dioxide.

After main fermentation is complete, the wine is racked off its lees-- the dead yeast cells and other strong matter that have settled at the bottom of the tank-- and a mix of yeast and sugar (the liqueur de tirage) is included to it. The red wine is then bottled and the liqueur de tirage triggers a 2nd fermentation process inside the bottle.

This secondary fermentation takes around 2 weeks and during this time, the yeast cells transform the sugar into alcohol and carbon dioxide. The carbon dioxide is released from the white wine and ends up being caught in the bottle, producing the bubbles that are particular of champagne.

As soon as fermentation is total, the bottles are positioned upside down in racks so that the sediment produced throughout fermentation settles in the neck of the bottle. The sediment is then eliminated through a procedure called riddling, which involves the gradual turning of the bottles so that the sediment gathers in the neck. This procedure takes around three weeks.

Once the sediment has actually been removed, the bottles are topped up with a 'dosage'-- a mix of white wine and sugar-- and sealed with a champagne cork and wire cage. The amount of sugar contributed to the white wine at this phase figures out the sweetness of the last champagne.

The champagne is left to age for a minimum of 15 months. Throughout this time, the red wine goes through a process known as autolysis, throughout which the yeast cells break down and release flavour substances into the white wine. When the champagne has been aged for the minimum period, it is prepared for sale.