Welcome to part 2 of Bubbles for beginners. In the first part we looked at the main types of sparkling wine. Now we dive into the question that lies behind it all: where do the tiny bubbles actually come from?
The short answer is that the bubbles are not pumped in like in soda. They arise naturally along the way, and the way it happens actually has quite a lot to say about how the wine tastes. Let us take it slowly and without technical contortions.
What you will learn
- How the bubbles get into the wine in the first place
- The difference between the two most important methods
- Why the method affects the style and the taste in your glass
The bubbles come from an extra fermentation
All wine starts with a fermentation, where the yeast turns the sugar in the grape juice into alcohol. Along the way a gas is also formed, carbon dioxide, but in ordinary still wine it escapes.
The secret behind bubbles is that you give the wine an extra fermentation, a kind of round two. You add a little sugar and yeast to the finished wine and seal it in, so the gas cannot escape. Instead it is trapped in the wine, and it is precisely those trapped bubbles you see rising up when you pour.
Think of it as a small, controlled fermentation in a closed space. Because the gas has nowhere to go, it becomes part of the wine. The decisive choice now is: where should the extra fermentation take place? In the bottle, or in a large tank? This is where the two main methods part ways.
The traditional method
With the traditional method (you will also encounter it as méthode traditionnelle or champenoise) the extra fermentation happens inside the individual bottle. The wine is put into the bottle together with a little sugar and yeast, the cap is put on, and then the bubbles are allowed to form precisely where they will stay.
What is special is that the wine is then allowed to rest on the spent yeast lees for a long time afterwards, often for several years. The long resting time gives the wine small, fine bubbles and some quite characteristic aromas and flavours that recall freshly baked bread, brioche and toasted nuts. It is the warm, yeasty note that many know and love in, for example, champagne.
It is a careful and time-consuming way to make bubbles. Champagne is always made this way, and so are French crémant and Spanish cava. The result is often a wine with depth and a creamy sense of bubbles that are fine as a whisper rather than a fizz.
The tank method
The other route is called the tank method (in Italian and French you may know it as Charmat). Here the extra fermentation does not happen in each individual bottle, but in a large, closed steel tank, where many litres of wine get bubbles all at once. Only afterwards is the wine bottled under pressure, so the bubbles come along.
This method is faster, and because the wine does not rest long on the yeast lees, it retains a cleaner and fruitier character. You less often get the baked, brioche-like notes. Instead the grape's own freshness comes forward, often with aromas of flowers, pear and citrus.
The best known wine from the tank method is prosecco from Italy, made from the grape Glera. The style is light, fruity and festive, and it is probably no coincidence that prosecco in particular has become the darling of everyday bubbles.
What it means for the taste
So why should you, as a beginner, worry at all about where the fermentation takes place? Because it gives you a little key to choosing by taste.
If you want a wine with depth, fine bubbles and a warm note of bread and nuts, then the traditional method points that way. If you would rather have something light, fresh and fruity that tastes of flowers and fruit, then the tank method is a good place to look.
These are two different moods rather than a ranking. One is not finer than the other, they simply suit different cravings and different evenings. And once you know that the method leaves its mark, the labels suddenly begin to make more sense.
In short
- The bubbles arise from an extra fermentation, where the gas is trapped in the wine instead of escaping.
- With the traditional method the extra fermentation happens in the bottle, and the long rest gives fine bubbles and notes of bread and brioche.
- With the tank method the fermentation happens in a large tank, which gives a fresh and fruity style.
- Champagne, crémant and cava are made traditionally, while prosecco is made by the tank method.
- The method is a useful key to choosing: depth and bread, or freshness and fruit.
Frequently asked questions
Are bubbles from the tank method of poorer quality?
No. It is just a different style. The tank method highlights the grape's freshness and fruit, while the traditional method gives depth and baked notes. Both can be well made and lovely, it is about what you are in the mood for.
Why do some bubbles taste of bread or brioche?
That comes from the wine having rested for a long time on the yeast lees after the extra fermentation, as happens with the traditional method. The warm, baked note is one of the hallmarks of, among others, champagne.
Ready for the next step?
Now you know where the bubbles come from, and why the method colours the taste. In the next part we look at a word you encounter on almost every bottle, namely brut, and what it actually says about the wine's sweetness. Read along in Dry or sweet? Understanding brut.
Do take your time to taste your way forward and feel the difference between a fresh, fruity style and one with more depth. You are welcome to drop by our selection of mousserende vin whenever the urge strikes. And remember that the best bottle is the one you yourself enjoy, together with the food and the company you are fond of.