What Makes Sparkling Wine So Bubbly?

As you pop a bottle of bubbly to toast the summer, have you ever stopped to wonder how they get the bubbles in sparkling wine?

In bubbly there are two fermentations, instead of the one that occurs in still wine.

“One in the tank to create the base wine, then we take those base wines and blend them together and put them in the bottle with a little bit of sugar and yeast,” said Craig McDonald, winemaker at Trius. “It is that combination that creates the fermentation and the CO2 is trapped in the bottle, creating the bubbles.”

In the traditional way of making sparkling wine – think Champagne — that second fermentation happens in the bottle. Since the bottle is sealed up, carbon dioxide produced during that fermentation dissolves into the wine making it sparkle.

The bottles are gradually tipped forward so the lees (dead yeast and sediment) collect in the bottle’s neck. The necks are frozen and disgorged, allowing the frozen chunk of lees to pop out. Before the wine is corked, the neck of each bottle is spiked with the dosage – a mixture of wine and sugar. This will determine the wine’s final level of sweetness.

In a fizzy wine like prosecco, the second fermentation happens in a tank rather than the individual bottles. This is known as Charmat or tank method and it is cheaper and faster than the traditional method but just as delicious. The flavour of these wines tend to be simpler and fruitier.

And there you have it!