In a nutshell
Sparkling wine is usually white or rose and can be made from both white and red grapes. There are many methods of production. Sparkling wine was first produced in the Champagne region of France. It’s a recent creation that first appeared around the 17th century that became immensely popular, very quickly. Today, Italy is one of the main producers of sparkling wine, including the well-known Prosecco and Franciacorta and Lambrusco. Read about our sparkling wine recommendations with our Sparkling 101 guide [link to article]
All methods of production
Putting fizz inside a bottle is not an easy task. The main methods of production are the Traditional method, the Charmat or Tank method, the Transfer method, the Carbonation and the Ancestral method.
Charmat Method
The second fermentation happens in a pressurised tank (which is why this method is also referred to as the tank method). Wines made this way have a fresh and fruity character. Prosecco is the most well-known wine produced with the Charmat method.
Transfer Method
The second fermentation happens in bottle. When it is time to remove the yeast cells, instead of dealing with every single bottle, the winemaker empties them in a pressurised tank and filters out the yeast cells. The result is a more mature wine than the Charmat method, but more cost-effective.
Carbonation
This process is the same as with soft drinks. There is no secondary fermentation. Instead, carbon dioxide is pressured in the base wine, where it gets dissolved. The bubbles here are larger and disappear quickly.
Ancestral Method
With the rising popularity of natural wines, this style has become increasingly common. There is no second fermentation here. Instead, the wine is bottled before the primary alcoholic fermentation is complete. It will therefore finish inside the bottle, creating bubbles.
Traditional method
This is the most respected of all methods for producing sparkling wines. It not only requires great quality of base wine but also precision winemaking and is labour intensive. The most well-known sparkling wines produced with the Traditional method are Champagne in France, Franciacorta in Italy and the Spanish Cava. Here are some more details on how it’s produced.
Harvesting & Pressing of Sparkling wine grapes
The grapes used for sparkling wines are the ones found in the Champagne region of France; Chardonnay, Pinot Noir and Meunier. These grapes retain acidity very well, a prerequisite for good sparkling wine.
Normally, grapes are harvested at about 11% potential alcohol, since sugar will be added for the second fermentation. Harvest is generally done by hand.
The grapes are pressed as soon as they reach the winery with a vertical or pneumatic press. These presses are preferred because they are gentle and won’t extract colour and tannins.
First fermentation & Blending of Sparkling wine grapes
The first fermentation is performed quickly at a higher temperature than white wines. The goal is to avoid fermentation aromas.
Once the base wine is ready it has to be clarified, before going in the bottle. That’s when the winemaker has to also blend the different base wines. Blending is done not only with different varieties and parcels but also with different vintages. Sparkling wine is expected to have consistent quality and flavour which makes blending particularly important, but it’s the most difficult step of the process.
Tirage & Bottling
Sugar, yeast and a clarification agent (usually bentonite) are added at the base wine before bottling. The mixture is called “liqueur de tirage”. The wine is then bottled with a crown cap for easy removal.
The yeast used here is particularly strong because it has to ferment in an unfavourable environment with high alcohol and increasing pressure.
Second fermentation
The bottled wine is stored horizontally in conditions that favour alcoholic fermentation in the dark at around 18-20 degrees.
The second fermentation is much slower than the first. It lasts approximately 6 to 8 weeks until all the sugars have been converted into carbon dioxide and alcohol. The sparkling wine will have been fermented dry.
After the fermentation is complete, all the yeast gradually falls as sediment in the bottom of the bottle.
Aging
The yeast that has fallen at the bottom of the bottle, called lees, is key to the character of the sparkling wine. As time passes, the yeast cells break down releasing proteins and flavours. The more the wine stays in contact with the lees, the more complex these aromas become.
The lees are responsible for flavours such as brioche and toast. The mouthfeel becomes very creamy and smooth.
Riddling
The sediment inside the bottle has to be removed before the wine is sold.
The first step is to move it from the side of the bottle to the neck, for easy removal. This happens by gradually turning the bottle sideways and towards the neck. The process is called riddling and can take one to two months.
As it is very labour intensive to do by hand, most companies use a contraption called a gyro palette that takes out the hard work!
Disgorging & Dosage
The sediment of the secondary fermentation is at the neck of the bottle after riddling and disgorging is performed to remove it. The neck of the bottle is cooled down so that the sediment freezes. The crown cap is removed and the pressure inside the bottle pushes the iced sediment outside.
Since some juice has been removed, it has to be filled up again. Now is when the sugar level of the sparkling wine is adjusted. Liqueur de dosage - typically a blend of the finished wine and sugar - is added to replace the volume lost with disgorgement and to sweeten the wine, if desired.
Corking & Labelling
After the bottle is filled with the liqueur de dosage, the sparkling wine is ready. The cork is put in place and secured with the little metal wire cage so that it will remain stable during handling and shipping.
After, the labels and capsule are applied. Some traditional method sparkling wines will label the date of secondary fermentation and the date of the disgorgement. This helps to distinguish between the lots, especially with the non-vintage sparkling wines.
