(Champagne method), also called Methode Traditionelle.
There are 4 main methods of making sparkling wine:
- carbonation - like soft drink.
- tank fermentation (Charmat method) - the wine is put through secondary fermentation in a bulk tank and then is bottled under pressure
- transfer method - the wine is put through secondary fermentation in the bottle, then all the bottles are emptied into a tank and the yeast sediment is filtered out. It is then rebottled under pressure
- Champagne method (Methode Champenoise) - the wine is put through secondary fermentation in the bottle, and the wine stays in this bottle with the naturally produced bubbles until the consumer drinks it. The means of getting the yeast out of the bottle is detailed below.
All Anderson Sparkling wines are made using the traditional Champagne method.
Once the base wine is made, it is prepared for bottling in a process called "tirage". Basically, the wine is mixed with an active yeast culture and a specific quantity of sugar so that once it is in bottle it will ferment. Carbon dioxide gas is a by product of fermentation and this is trapped inside the sealed bottles, producing bubbles.
This secondary fermentation in the bottles is over in a few weeks (all the sugar is used up by the yeast). The longer the yeast cells are left in the bottles after the fermentation is complete, the more flavour, complexity and texture they give to the wine. Wines which have been stored on yeast lees for a number of years are very creamy and complex.
The yeast sediment must be removed from the bottles before the wine is consumed. This is best done soon before consumption, as after a year or two of having the yeast taken out the wine will start to lose freshness and bubbles. At Anderson winery we are continually doing the following process so that whatever you buy from us is fresh.
Firstly the yeast needs to be accumulated in the neck of the bottle. The wine remains in the same bottle it was bottled in, and only the yeast is taken out.
This is achieved using wooden racks ("riddling racks" - pictured) which hold the bottles at an angle. The bottles are turned and tilted in a specific way to get the yeast to slowly accumulate in the neck over several weeks. This is called "remuage" or "riddling". Some larger wineries use a faster, less labour intensive method involving stacking the bottles in large wire crates which are automatically turned by a machine.
Once all the yeast is settled in the neck it is time to remove it. This is called "disgorging". The bottles are removed from the racks and kept upside down to prevent mixing of the yeast sediment. We put them in the coolroom overnight to prevent them gushing when they are opened.
The next morning the bottles are loaded into the "neck freezer", which contains a freezing solution at about minus 22 degrees C. Just the necks of the bottles are submerged in the solution, and this freezes the sediment in about 5 minutes. The bottles can then be turned up the right way without mixing up the sediment, and the cap taken off. The pressure in the bottle blows out the frozen plug of yeast.
A small amount of liqueur is then added (even brut Champagne has about 8g/L sugar as the bubbles make the wine taste excessively dry). We just use sugar syrup as the liqueur, but other wineries sometimes use a sweetened older wine.
The bottle is then topped to the right height and the cork and wire put on. Then it's ready to drink!
See the video disgorging in action.