What is MLF in winemaking?
WINEMAKING. Introduction. Malolactic fermentation (MLF) is a secondary bacterial fermentation carried out in most red wines and some white and sparkling wines. It often occurs naturally after the completion of primary fermentation or can also be induced by inoculation with a selected bacterial strain.
How long should malolactic fermentation take?
about 4 weeks
If all conditions are optimal, a malolactic fermentation should take about 4 weeks to complete. It may not be wise to try to stretch a culture to grow to do larger gallonage than designed because the bacteria is slow to grow.
What does malolactic bacteria do in wine?
Malolactic fermentation takes the edge off a wine’s acidity by converting the sharper malic acid into the softer lactic acid (hence the name malolactic), which rounds out the mouthfeel and makes a wine more accessible.
Do all wines go through malolactic fermentation?
No, not at all. MLF is generally undesirable in some styles of wine, particularly aromatic and zingy, high acid whites such as Riesling and Sauvignon Blanc. Winemakers can inhibit malolactic fermentation by adding SO2 to wines post-fermentation or through the use of enzymes, such as lysozyme.
Is malolactic fermentation necessary?
For many wines, malolactic fermentation is essential to the process of turning grape juice into fine wine.
When should I add malolactic bacteria to red wine?
The most-accepted rule of thumb is to wait until the end of primary fermentation before adding the culture. Malolactic activity can be detected by the presence of tiny carbon-dioxide bubbles. When the bubbles stop, MLF is complete.
Should you Stir wine during malolactic fermentation?
Do not stir during MLF. Add SO2 immediately following the completion of MLF (when Diacetyl is highest). Complete MLF, then monitor diacetyl and add SO2 when it reaches the desired level.
Does malolactic fermentation happen naturally?
Malolactic fermentation can occur spontaneously, but it’s best to conduct it yourself. MLF is generally used for dry red wines but can also enhance some dry white wines, such as Chardonnay, Sauvignon Blanc and Pinot Gris. MLF is not recommended for sweeter wines, like Riesling, Gewürztraminer and Muscat.
What does malolactic fermentation smell like?
Lactic acid bacteria (LAB) are used to convert malic acid to lactic acid during malolactic fermentation (MLF). Caution must be taken to ensure that MLF is complete before bottling or that MLF has been properly inhibited, followed by sterile filtration. Smells like rancid butter, buttery, butterscotch.
Which wines undergo malolactic fermentation?
What Wines Undergo Malolactic Fermentation? Nearly all red wines and some white wines (such as Chardonnay and Viognier) undergo malolactic fermentation. One way to recognize MLF in a wine is to note if it has a creamy, oily mid-palate texture. This can indicate malo (or also lees aging).
How do you know when malolactic fermentation is complete?
The most-accepted rule of thumb is to wait until the end of primary fermentation before adding the culture. Malolactic activity can be detected by the presence of tiny carbon-dioxide bubbles. When the bubbles stop, MLF is complete. This should take one to three months.
What does malolactic fermentation taste like?
Malolactic fermentation tends to create a rounder, fuller mouthfeel. Malic acid is typically associated with the taste of green apples, while lactic acid is richer and more buttery tasting. Grapes produced in cool regions tend to be high in acidity, much of which comes from the contribution of malic acid.
How do you know if malolactic fermentation has started?
Can you add too much malolactic bacteria to wine?
Temperatures below 58oF or 14oC strongly inhibit MLF (malolactic fermentation). 6. One cannot add too much excess bacteria to a wine. However, do not try to stretch the culture beyond it rated gallonage.
Can malolactic fermentation happen in the bottle?
ML can take place in a tank, in a barrel, or in a bottle. It’s not necessary to the winemaking process, but it’s a very popular method. Most red wines and many white wines are intentionally put through ML to enhance stability and complexity. However, if ML takes place in a bottle, the results can be disastrous.