Are two fermentations better than one?

Sparkling wines in a riddling machine prior to being disgorged, corked and caged.

Anyone who drinks wine is likely aware that the alcohol is a product of fermentation. When yeast is introduced to a liquid that contains sugar it goes to work and starts to eat that sugar, leaving by-products of alcohol, heat and carbon dioxide. Most wine is made by using specific types of commercial yeast, which helps the winemaker have a clue about what the result might be. Some wineries are now avoiding commercial yeast, relying on the wild stuff that is in the air, on the grapes, even on the winery walls and floor. It’s a bit riskier, or maybe even a lot riskier, but every winery is looking for some sort of edge that sets its products apart from others.

So yes, Baillie-Grohman wines are made with commercial yeasts that we have come to know and love here at the winery, because they help us make the wines that our customers have come to expect. But did you know that some of our wines go through not one, but two fermentations?

When making our delicious Tetes de Cuvée sparkling wine (which, sadly, sold out last weekend!), the first step is to make wine from the grapes and yeast. After the wine has reached a point that satisfies the winemaker it goes into bottles—not the usual wine bottle, but a significantly thicker and heavier one. The contents are about to create a whole lot of pressure in its bottle! Before it is capped, a small dose of sugar and encapsulated yeast (yeast coated with an organic product to form tiny beads) is added to the bottle, which is then sealed with a metal crown cap, the older style closure that does not twist off.

Many months, or even years later, the yeast having worked its magic by creating CO2 bubbles in the liquid, the spent yeast is removed (we’ll get around to that process in another entry), the bottle gets a little top-up of Chardonnay, a cork is inserted and a wire basket is tied tightly to hold the cork in place.

This particular process of making sparkling wine is called méthode champenoise, or now, more commonly, méthode traditionelle, which we know in English as the Champagne, or French, method.

Not surprisingly, the lore of Champagne-making is rich, given that it has been going for more than 300 years. The Benedictine monk Dom Pérignon is incorrectly credited with “inventing” sparkling wine, but he actually did make many contributions to improving the wine-making processes. He is often also attributed with the quote, “Come quickly, I am tasting stars!” Apparently that phrase was first used in a 19th century ad campaign, though. The bubbly that still bears his name is mighty fine stuff, though!

What other wines undergo a second fermentation? Our Chardonnay is aged in French oak barrels, in which malolactic fermentation is fostered, and the same goes for our reds—these wines all benefit from the process in which tart-tasting malic acid is converted to the softer-tasting lactic acid. These fermentations, unlike the yeast-induced ones, are undertaken by a specific family of lactic acid bacteria. Personally, given the great effect this bacteria has on wine, if I ever go to a doctor and am told I have a bacterial infection, I’m going to ask if it is lactic acid bacteria. I could probably benefit from a little softening at times!

The most obvious result of malolactic fermentation is the shift from malic acid, which tastes most prominently of green apples, to lactic acid, which imparts a luscious butteriness.

Anyway, the whole point of this discussion is that we should not simply assume that the yeast-induced process is the only time that all of the wines we enjoy go through a fermenting stage. One curious little fact is that yeast fermentation and malolactic fermentation can actually take place at the same time (winemaker Wes Johnson doesn’t allow that to happen at Baillie-Grohman, though). That concept gives me a flashback to the old Certs breath mint commercial, where the twin sisters chimed, “Two, two, two mints in one!”

“Two, two, two fermentations in one” does not, admittedly have the same ring to it, but it is another reminder that winemakers spend a lot of their time thinking about chemistry.

August 9, 2019