Winemaker Patrick Melley of Russian Hill Estate Winery just answered this question of Malolactic Fermentation. And for wine beginners (or intermediates, like me), this doesn’t get any better. As one of our clients, I get to edit for the winery on occasion. This was one of those times, but only on the technical business writing side for this one. not for winemaking.
In the past on this blog, I’ve discussed Malolactic fermentation, but only as it relates to white wines. For your benefit, I’ve reduced Malolactic fermentation, but only as it applies to white wine. (I’ve never had to explain ML regarding red wines, because I’ve always know it’s just done; no pomp and circumstance necessary… just done.)

So, White Wine and Malolactic Fermentation, According to Jo
It’s as easy as A + B = C
Acid + Bacteria = Cream
(Malic Acid + Bacteria = laCtic Acid, the same acid in Cream and milk.
If you didn’t know, now you’ve got it.
But, this doesn’t apply to red wine in the same thinking, I’ve just learned… not the same way as it does for white wine. So, what is it about with red wines? Patrick explained to me that it’s different for red wines, because we can’t say they have a “Creamy” texture. They are, however, softened. Patrick’s explanation.

PATRICK MELLEY ~ On Malolactic in Red Wines
It seems that many people are unsure what it is; although, it’s often referred to when discussing wine. It’s commonly referred to as either “ML” or “Malo.”
While most people know about primary fermentation, where yeast converts grape sugar into alcohol with the byproducts of heat and CO2 production, most don’t yet understand the role of Malolactic fermentation.
It’s similar to primary fermentation, in that there’s a biological conversion of one product into another. In the case of “ML,” the process is done by bacteria rather than the yeast, which does the work in primary fermentation. In ML the bacteria will naturally convert the Malic acid, which is found in grapes, into Lactic acid. The bacteria usually work at a slightly slower pace than yeast, so the conversion usually takes longer to finish than that of the primary fermentation.
Some of the reasons that a winemaker wants to convert the malic acid into lactic acid is that it makes the wine have a softer feel. And more important, it makes the wine more stable during its ageing and bottling.

EVER WONDER WHY THERE’S A FIZZINESS IN YOUR WINE?
If there’s remaining malic acid in the wine prior to bottling, the wine can become fizzy during certain conditions, such as exposure to heat. The warmth will activate the bacteria, which is normally in wine, and allow it to begin converting any remaining malic acid into lactic acid. If it happens while in a bottle, the cork will not allow the CO2 gases to escape. When the bottle is opened, it appears to be fizzy due to the trapped CO2.
The whole ML process has some very complex chemistry, and the above explanation is a very broad overview of the process. I hope this helps to get a handle on Malolactic fermentation. In the meantime, keep enjoying Russian River wines!!
So there you have it, straight from “Ask the Winemaker”
They are softer, but we can’t call a red wine creamy, now can we?
I recently bought some Raymond cabernet that was good but tasted and smelled a little like after-shave. I have also noted it in Oak Hill zins.
Could M-L fermentation be the cause of this?
Thanks
That’s a good question. Was the aroma floral? Not sure which aftershave, so I have no comparison. Wines are subject to their terroir. (any vines growing around Eucalyptus trees pick up that mint aroma, for instance. If your aftershave has floral notes, you’re comparing apples to apples…
You know it’s funny these past few weeks I’ve been testing my Barbera that I made in October waiting for Mallo to complete, all the notes that I previously took from previous wines I made, all the research I’m doing and then this add pops up on Google.
Barbara being naturally higher in acid than other reds acts a little bit differently and from my Accuvin chart not being at total 0 it is ready to be racked.
I didn’t know that about Barbera being naturally higher in acid. Good info to share.
So, if racked, do you think it will have a bit of spritz?