Champagne: With Or Without Malo?

  • By Michelle Bouffard
  • 22 Feb 2021
  • 5 MIN
  • Level 201
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Champagne tasting at Selosse - Credit : Michelle Bouffard

Malolactic fermentation (MLF) is a conversion of the harsher tasting malic acid to the softer tasting lactic acid. It usually happens after fermentation has been completed and, in some cases, simultaneously. A winemaker can either encourage MLF or block it. This decision has an important impact on the final style of the wine as it particularly influences the total acidity, the texture, the flavours and the ageing potential of the wine.  

MLF has always been a key component in defining the style of a Champagne producer, and with climate change bringing warmer temperatures and therefore decreasing the total acidity in the grapes, MLF is more than ever a topic of discussion in the region. 

A Look At The Science Behind MLF 

For MLF to occur, the wine needs to be at a temperature of between 18 to 20-degrees Celsius and at a pH between 3.2 and 3.5. The total sulfur dioxide (SO2) should be ideally be below 30 mg/L. Those conditions encourage the growth of the lactic acid bacteria (LAB) which are responsible for the conversion. There are many different species of LAB including Lactobacillus, Pediococcus, and Oenococcus oeni. MLF can happen naturally, or a producer may inoculate the wine with lyophilized Oenococcus oeni bacteria to accelerate the process.  

MLF has a big influence on the style of the wine. First, it decreases the total acidity (TA) by 1 - 3 g/L , softening the wine. Then the production of glycerol and polysaccharides during MLF contribute to increasing the body and the texture while the production of diacetyl releases flavours such as butter and hazelnut. 

The Case For Inducing MLF 

MLF is a helpful winemaking tool in a cool region such as Champagne where the natural acidity tends to be very high. Many producers do MLF as it makes the wine rounder and more approachable to drink. This is especially helpful for non-vintage Champagne meant to be enjoyed upon release. It is one of the reasons Hervé Dantan decided to do 20 - 25% of MLF for the NV Black Label when he took the job as chef de cave at Lanson in 2014. Previously, Lanson had always blocked MLF. 

The Case For Blocking MLF 

But blocking MLF also has its virtues and it gives a completely different profile to the wine which is desired by many, especially for producers seeking to make wine with ageing potential. To prevent MLF, a few key points need to be followed:  

The temperature of the wine should be kept at somewhere between 10 and 14 degrees Celcius and the total S02 above 25 mg/L. The pH of the wine should ideally be below 3.2. While wine with no MLF retains freshness and has higher acid, the structure provides the necessary elements to age Champagne. One only has to think of how tight the great vintages of Krug, Salon, and Selosse are in their youth, yet how complex they become after many years in the cellar. 

On The Subject Of Climate Change 

The topic of whether to let MLF occur or not has taken another angle of discussion with the increasing temperatures brought about by climate change. The Comité Interprofessionnel du Vin de champagne (CIVC) says that in the last 30 years, acidity has dropped by 1.3 g/L and the overall temperature increased by 1.1 degrees Celsius. The decrease of the acidity in the grapes has convinced many producers like Guillaume Tournant-Lemaire of Champagne Lemaire that the future of great Champagne is without MLF. However, Jean-Baptiste Lecaillon, chef de cave at the highly regarded Champagne house Roederer, has more nuances in his dialogue. In warmer vintages like 2015 and 2018, he likes to block MLF to keep the freshness. He finds it produces a wine with a salinity on the finish, contributing to the length of the Champagne. But in cooler vintages, Lecaillon favours MLF as it gives depth and roundness to the wine. 

Looking To The Future 

Blocking or encouraging malolactic fermentation is one of the many decisions which contribute to the final style of Champagne. Without a doubt, great wines have hailed from both techniques.  As climate change continues to have repercussions on the winemaking of the region, it will be interesting to follow how established Champagne producers change their winemaking techniques. 

Champagne tasting at Selosse - Credit : Michelle Bouffard