Friday, January 22, 2010

Malolactic Fermentation begins

Well, about a week ago I inoculated the wine with a Malolactic fermentation bacteria. This is an important step in many red wines. While the primary fermentation is accomplished by yeast, converting the sugar into ethanol, this malolactic ("secondary") fermentation is accomplished by a special kind of bacteria. The bacteria converts harsh malic acid into softer lactic acid. It releases CO2 at the same time so the wine bubbles as it does with primary fermentation. Malolactic fermentation ("MLF") makes many wines taste better because the malic acid present in the wine is very tart (think of the crisp acidity of an apple). Many wines (mostly white wines) benefit from this acidity, but in a red wine, the taste is usually considered undesirable. The MLF process naturally converts this tart malic acid into a soft and buttery lactic acid. The pH doesn't change, because you are just converting one kind of acid to another, but the taste changes.

Depending on the fermentation temperature and the amount of malic acid present in the wine, the MLF process can take from a few weeks to a few months. I have it from a reliable source that many of the 2008 Burgundys underwent MLF that took nearly a year!

I expect my MLF to take around a month. For now, I just need to keep watching the bubbles to see when the process slows down.


No comments:

Post a Comment