Monday, February 13, 2012

Understanding the Malolactic Coma

January and February are traditionally considered to be the "slow season" at Clos Pegase, because that is when our production team stops to take a minute to catch their breath after the past Harvest.

That doesn't mean that the cellar is a ghost town. The action shifts from the crushpad in September, to the cellar in November through the beginning of the new year, and inevitably the focus lands in the lab in January and February.

While our winemaking team keeps an eye on the vineyards, glancing at the weather report and its lack of rain (the exact opposite of what we did in October of 2011 when we desperately wished for rain to stay away), they are keeping their other eye on the wines that we are getting ready to bottle, not to mention the wines from 2011 that are in barrel (gotta make sure everything is progressing in the right way, you know!)

In order to get a better idea of what type of things go on in the cellar in the "off-season" I headed in to chat with Winemaker, Richard Sowalsky, where he was full of production-world gems.

This time of year, Richard explained, malolactic fermentations are usually wrapping up in the cellar and the team has been keeping close watch to make sure the acid levels are at the desired levels, achieved via this process. What are the desirable levels? So glad you asked.

Before I tell you, I will admit. I'm a rookie at this production stuff (me: grapes get smashed, juice ferments to alcohol, bottle it up and enjoy. Simple. Now we know why science wasn't my strong suit.) So I wanted to know what this malolactic fermentation stuff was all about.

This fermentation, or more accurately, chemical conversion, is the process during which malic acid is converted to lactic acid. For everyone reading this who feared chemistry was a communications major like me, this is like converting the tart taste of apples to the less tart taste associated with sourdough bread. You introduce some "desirable bacteria" into the wine (or use bacteria naturally on the grape skins or in the winery) and they take care of the conversion, a process which naturally de-acidifies the wine. Without ML (as I call it, so I can sound like I know what I'm taking about after my crash course with the production team) many of the wines would taste sharp- great for wines known for crisp acidity like sauvignon blanc; not so great for cabernet sauvignon or merlot.

This conversion happens with almost all wines in our portfolio, with the exception of our Sauvignon Blanc, Vin Gris Rosé and The Portico. (Our SB is known for its crisp acidity so if we allowed malolactic fermentation to take place, that lovely acidity would be gone. Insert sad face here.)

But back to the science of this winemaking stuff. It was at this point in the conversation with Richard that he drew me a couple of molecules on a piece of paper, complete with carbon, hydrogen and oxygen atoms. This was in order to illustrate the ML conversion. I'm going to spare you this part, because it was here was I finally understood what he meant when he referred to this process as the "malolactic coma."

Basically, he went into a whole bunch of science-related topics about bacteria eating carbon chains and stabilizing the wine and I was furiously writing notes down, stopping him every couple of minutes to clarify what he'd just explained.

And I was still confused.

In order to save you from entering into the malolactic coma yourselves (you're welcome for taking one for the team), I'm going to just give your the jest of it, with some history mixed in for good measure:

Wine has three types of acids in it:

  • tartaric, which is pretty stable and acceptable in the wine
  • malic, which is unstable and can be less desirable because of the tart flavors it imparts (unless you're making sauvignon blanc, or another "crisp" varietal)
  • citric, though this is found in very minute amounts.

So, you have these types of acid in the wine and malolactic fermentation is the method that leaves the tartaric acid in tact but more importantly converts the malic acid into lactic acid. During ML, the citric acid also runs the risk of becoming diacetyl. Diacetyl is what causes the super buttery, nutty, oaky flavors in wine that overpower everything else. And if the wrong type of "desirable bacteria" is introduced, diacetyl could be an issue.

Enter the history part of this lesson.

Back in the day, in the Champagne region of France, they were making lovely sparkling wines, but diacetyl (read: buttery, oaky flavors) was overshadowing the delicate bubbles. Some smarty wine scientists then developed a good bacteria that could be used in the ML process that would not leave diacetyl behind as a bi-product and thus, a "desirable bacteria" was born. Then all the winemakers from the Champagne houses rejoiced.

But back to our story.

We choose to mimic the Champagne method of ML because it allows us to emphasize the vineyard fruit and the place from which our grapes come, rather than obscure the quality fruit. Since we age everything in oak barrels, we still have some of the hallmark qualities of varietals (toasty oak, vanilla, etc.) but can better balance those qualities with the fruit characteristics, giving our wines a sense of place while keeping it in balance.

So that, my friends, is the short version of malolactic fermentation, believe it or not.

Trust me, be very glad you didn't get the whole science version. I'm still recovering from the high school chemistry flashbacks induced by those molecule drawings...

-Colleen LeMasters
Clos Pegase Winery

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