Carbonic Maceration - Molecular Magic!

Carbonic Maceration is a process which normally takes place during red wine fermentation and produces a wine which is fresh and fruit-forward and low in tannins. This process happens in a sealed tank with the whole cluster of red grapes filled with carbon dioxide. So, fermentation takes place in an oxygen-poor (Anaerobic) environment. 

The anaerobic environment causes the grapes to release enzymes which helps to start intracellular fermentation inside the berries. As the fermentation starts inside the berries it releases carbon dioxide and creates an environment which is rich in carbon dioxide. As the whole process of fermentation happens inside the berries, they burst when the alcohol reaches a certain percentage.

@Carbonic Maceration.
Image Credits - Decanter.com

So, what changes carbonic maceration does in a wine?

As mentioned before carbonic macerated wines have low tannins and lighter colour, the reason for the same is, for a wine to have high tannins and strong colour it needs to have a good amount time for skin contact during fermentation, but, here the fermentation happens in the intact berries and it gets lesser time to spend with the skin, which makes the wine to be low in tannins and lighter in colour. This process not only affects the tannins and colour but, also the aromas and flavours.

Not all grape varieties are suitable for this process. The popularly used ones are Gamay, Pinot Noir, Carignan, Sangiovese & Mouvedre. Aromas and flavours achieved from the process are:

• Bubblegum
• Banana
• Kirsch
• Cinnamon
• Strawberry

Louis Pasteur a French scientist was the first to study about the process of carbonic maceration and its effects on the flavour of the wine versus the regular fermentation. In 1934, another French scientist Michel Flanzy was trying to perfect the preservation of the grapes with Carbon dioxide. He noticed various changes the carbon dioxide gas made to the grapes, especially during the process of fermentation. 

Generally, this style of wine can be found all over the world but, one style which is famous all over is found in Beaujolais, Burgundy. For years Beaujolais has acquired its popularity from the red Beaujolais Nouveau wine. The wines which were made commercially popular by the genius of Georges Duboeuf who is also the largest producer of this wine. Nouveau is released on the 3rd Thursday of November, just a few weeks after the harvest. Beaujolais Nouveau was first allowed by law in 1951; it surged from the bistro tables of Lyon to worldwide popularity in the 1970s and ‘80s. 

It started gaining popularity when the idea of a race to Paris carrying the first bottles of the new vintage was conceived and this attracted much media attention. By the 1970s, the race became a national event. The races spread to neighbouring countries in Europe in the 1980s, followed by North America, and in the 1990s, to Asia. The traditional slogan used in ad campaigns and marketing material - "Le Beaujolais nouveau est arrivé" (which translates to The new Beaujolais has arrived) was changed in 2005 to "Its Beaujolais Nouveau time".

@Les Vins Georges Duboeuf, Beaujolais Noveau.

Selling this young red wines by the means of the festival also helped some vintners to create cash flow shortly after the harvest, and also helped to acquire decent profits. Today a lot of vintners are making this popular red and is sold all over the world.

So, what is Semi-Carbonic maceration?

Today most of the producer used this process instead of the normal carbonic maceration. In this process, the vats are not filled with Carbon dioxide, but the whole cluster of grapes are left in the vat, most likely the grape in the bottom of the vat will get crushed by the weight of the grape above it. This releases the must and the ambient yeast start fermenting the juice and in turn, it creates carbon dioxide and alcohol. This carbon dioxide achieved from the fermented juice fills the vats and helps to initiate the carbonic maceration inside the intact berries. This process is very similar to the usual process only a slight difference makes it different from the normal. 

Article By – Nikhil Surve, Certified Sommelier.