Malolactic Fermentation

I guarantee that most of you know what malolactic fermentation is, but I’ll bet most of you can’t explain it. And rightfully so. This is a tough subject and almost every winery you go to will explain it a little different. So, I’ll give it a go here.

For those who don’t know, malolactic fermentation is a process that most wine goes through either during or after alcoholic fermentation. This depends mostly on winemaker preference. The process uses bacteria to convert malic acid that naturally occurs in the grapes into lactic acid. In Chardonnay, where you know lactic acid in wine the best, this fermentation can lead to the buttery characteristic you all know from California Chardonnay.

Malic acid is a harsh, strong acid that, again, naturally occurs in the grapes. For comparison, malic acid is most commonly found in green apples, salt and vinegar potato chips and all those sour candies. Getting an idea of how this acid tastes?

Lactic acid is, of course, the acid we find in dairy products – everything from milk to butter. A softer acid that’s much more pleasing on the palate.

So, the process of malolactic fermentation makes wine easier to drink. Almost all wine (red and white) goes through the process. However, most Sauvignon Blancs, Rose wines and some dessert wines do not go through the process. Here, in America, a winemaker can choose whether they want to put their wines through this process. In other parts of the world, there are regulations that may restrict the winemaker from meddling with the process. You see, malolactic fermentation can (and has for hundreds of years) happen on its own. But here, we choose to control it.

Alright, so I want to share with you what I share with lots of guests that come into the winery. When I think of malolactic fermentation, I usually think of Chardonnay. And I’m usually pouring Chardonnay when I talk about it. I break it down like this:

I always think of Chardonnay on a sliding scale of dairy products.

*Nonfat milk

*Whole milk

*Half and Half



Now, let me be clear. Obviously, you won’t be tasting any of these items in your wine, but it’s all about the texture. Think of the texture of all the different dairy products and how they would feel in your mouth and coat your tongue. That is what malolactic fermentation is all about.

You will find all of these textures in different California Chardonnays, mostly depending on climate and how much of the overall wine goes through the process. A winemaker can choose to put some or all of the wine through malolactic fermentation. For instance, to end up with a product that falls more in the half and half category, the winemaker may choose to only convert half of the wine. That leaves half with lots of malic acid. When the two are combined before bottling, instead of what could have been a butter texture, the wine falls more towards the middle.

But some Chardonnays taste like butter, right? Right. Here’s the deal. When you actually taste butter in the wine that usually means that there is some leftover bacteria from the malolactic fermentation. Many people love this characteristic and so lots of wineries have followed this formula. It’s not what I look for. I’m not afraid of a butter texture, but I’ll leave my butter flavor from real butter melting on my freshly baked sourdough bread.

Next time you put that Chardonnay in your mouth, don’t just assume butter right away. Stop and think about where it might fit into the scale above. Yes, many of them are towards the butter category, but many of them fall somewhere else on the scale and our minds are trained to think Chardonnay = butter.



Leave a comment

Filed under Uncategorized

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s