Wine kits are great for experimenting. Whether you want to swap out the yeast, try a split fermentation with multiple strains, or use different types of oak kits are the most economical wine making medium to experiment on.
Malolactic fermentation, however, is not something that should be experimented with on most wine kits. In fact unless your kit came with malolactic bacteria I suggest steering clear of MLF altogether. Why?
What Malolcactic Fermentation Does to Kit Wines
Lactic acid bacteria, such as the strain of lactobacillus shown here, consumes malic acid and converts it into lactic acid. By comparison lactic acid is weaker than malic acid which is exactly why you would perform malolactic fermentation in the first place.
An overly acidic wine can be put through malolactic fermentation to reduce the total acidity. Most wine kits, however, have been tartrate balanced at the time of manufacture. This process increases the amount of malic acid in the wine making juice.
By performing a malolactic fermentation you will not only be reducing an already balanced acidity, you will also be converting the bulk of the acid present into lactic acid. This can drastically lower your acidity and raise the pH, sometimes as high as 3.8.
The result will be a flat and uneventful wine. Lactic acid also has a buttery flavor to it that can complement some wine is moderation. Creating a wine that has a majority of lactic acid in it may come out tasting really buttery.
Malolactic Bacteria and Sorbate
Another measure that kit manufacturers take to prolong the shelf life of their product is adding sorbate to the unfermented juice. Additionally most kits also call for sorbate to be added after primary fermentation to prevent further fermentation once the wine has been bottled.
It turns out that malolactic bacteria interacts with sorbate to produce a chemical known has hexadiene. The presence of this in wine causes rotting geranium odors to form. This is both disgusting and cannot be fixed once it sets in.
Some wine making sites suggest that you can successfully perform malolactic fermentation on wine kits provided that you delay the addition of sorbate until after malolactic fermentation has completed. This seems risky though given that there may be some sorbate already in there and because there may also be an abundance of malic acid. This is probably something that will vary from one kit manufacturer to another.
For more information on malolactic fermentation check out What is Malolactic Fermentation?.
Photograph used under Creative Commons licence. Photgraph by: Riccaroariotti