I’m revisiting this topic from an earlier blog post, because I recently hosted an “All Things Bubbles” #VirtualVino class and I thought it was worthwhile to come back to it. Wine education can be a bit daunting, but it doesn’t have to be! I like to take wine concepts and break them down in digestible, easy to understand nuggets.
Most people can wrap their heads around how to make alcohol. It’s a simple fermentation process. Yeast converts sugar (i.e. grape juice) into alcohol (i.e. wine). Bada-bing, bada-boom, you have yourself some vino. If we’re talking about spirits, a distillation process happens after the fermentation, but that’s a different topic!
I have always LOVED bubbly. All kinds of bubbly: serious Champagnes, nutty Cavas, or fruit-forward Prosecco. Team bubbly all the way. As a novice wine drinker years ago, I did wonder how the heck bubbles happened and why the bottles literally didn’t explode from the pressure. As I pursued my wine education, I began to understand the process to make bubbles happen in wine!
Here are the steps to get bubbles in bubbly. What I’m going to explain to you is the “traditional method” or the “methode Champenoise”. This style is in Champagne, Cremants from elsewhere in France, Franciacorta (sparkling wine from Lombardy, Italy), and with Cavas from Spain.
Start with a still, dry base wine (usually in stainless steel tanks) as described above. If you were making regular non-sparkling wine, you’ve reached the finish line.
That wine is then bottled with additional sugar and yeast (i.e. the liqueur de tirage) so a second fermentation can take place IN the bottle. A closure tops the bottle (usually a crown cap). The second fermentation creates carbon dioxide (CO2) inside the bottle as the yeast is eating the sugar. This CO2 has nowhere to go and essentially carbonates the wine and creates bubbles!
During this time period, yeast autolysis takes place. Yeast autolysis is when the dead yeast cells (i.e. lees) breakdown in the wine. The dead yeast cells impart autolytic flavors. This is pretty much what makes Champagne taste like Champagne. The flavors include yeastiness, toasty flavors, biscuit flavors, and doughiness. How much autolytic flavors the winemaker desires, will determine the length of time the wine is spent sur lie (i.e. resting on the lees). It can be anywhere from a few weeks to a few years!
Next is the riddling of the wine. The bottle is slowly moved from a horizontal to a tilted vertical position (manually or by machine). This moves the sediment to the top of the bottle.
Disgorgement follows in which the neck of the bottle is submerged in cold brine to freeze it. Once the closure is removed, that frozen sediment piece pops out.
A dosage (or a liqueur d’expédition) is added back to the bottle. This is a small amount of base wine and sugar. The amount of dosage added determines the level of sweetness of the wine. To keep the contents under pressure until the cork is popped, the bottle is then sealed with a sparkling wine closure (including the wire cage).
I recently opened this traditional method sparkling wine from a Spanish winemaking family who have been making Cava since 1872.
I found this wine crisp and refreshing and full of primary fruit aromas and flavors: citrus (lemon and grapefruit) and green apple. There is a distinct nuttiness, moving into a yeasty/bready note.
This method is used with Prosecco, many domestic sparklers, and with Lambrusco (a sparkling red from Emilia-Romagna, Italy)
Same as above. Start with a still, dry base wine.
The still base wine, yeast, and sugar additions are put in a sealed stainless steel tank.
The yeast and sugar initiate the second fermentation. This fermentation creates carbon dioxide (CO2) inside the tank as the yeast is eating the sugar. This CO2 has nowhere to go and creates bubbles!
The dosage (additional base wine + sugar) is added to the wine, and the wine is bottled under pressure.
With a tank method sparkling, the winemaker is generally aiming for a fresher fruit characteristic vs the autolytic flavors generated from the traditional method.
I recently opened this tank method Prosecco.
A bright and feminine wine, as I would expect from a Prosecco. Green fruit notes of apple and pear, plus a dominant white flower note (almost perfumed). An elegant, classy Prosecco.
So how do bubbles get into bubbly? It's due to the CO2 generated during the second fermentation (can be in bottle or tank). This CO2 cannot escape. The result: bubbles. Voila, you just upped your wine game!
On a bottle of sparkling wine, how many times does the wire cage have to be turned you get it off? Answer: Six…..always six turns.