Production Line of Champagne
Benjamin Cochain 2006
Introduction :
Champagne enjoys a reputation as one of the most well-known and sought after
sparkling wines usually consumed only on special occasions; few people enjoy the luxury of
champagne everyday!
The process of wine making was taken to a new level when in the 17th century a
Benedictine monk, Dom Perignon, noticed that in the spring time some wines refermented,
resulting in a build up of pressure from the release of carbon dioxide, CO2, causing the bottles
to explode! To combat this, the bottles were reinforced to give the familiar Champagne
bottle. The stopper used until that point was a simple wad of cotton that had been soaked in
oil. The first production of Champagne led to the introduction of cork stoppers. The cork
inserted into the bottle is always cylindrical but the pressure in Champagne bottles causes the
distortion as the cork is forced out of the top of the bottle during maturation.
Champagne is the most northerly of the major wine growing regions in France, and is
one of the oldest vineyards in Europe. Fossil evidence shows there were vines there millions
of years ago and the number was greatly increased in Roman times.
The trade name Champagne can only be used for sparkling wines produced in this
region, others have to use different brand names, e.g. Spunante from Italy and Sekt from
Germany.
1
The Champagne making process:
Harvesting
To obtain the name Champagne, the grapes must be harvest manually and the
harvesting must be done in one time to insure the homogeneity of the juice.
The juice of most grapes is white so the colour of the wine comes only from the skins.
Usually a blend of the juice of white and black grapes is used to make champagne. Blancs de
Blanc are the only examples made purely from white grape. Rose, or pink, champagnes are
produced by using some red skins as well as the white. The black and white grapes are grown
in separate vineyards throughout the region. For example, some black grapes are grown on
the slopes of the Montagne de Reims - a hill to the south-west of Reims with its southern
point at Epernay - and some white grapes come from the Cotes des Blancs, south of Epernay.
There are also extensive vineyards in the valley of the River Marne, downstream of Epernay.
Only Blancs de Blanc are made from white grapes only.
2
There is a wide variation from year to year in the quality of the grapes, and hence the
wines, that are produced because the vineyards are so far north and the weather is not
consistent. The best Champagnes are 'vintage', i.e. made almost entirely from wines of one
good year; non vintage Champagnes are a blend of good and not so good wines.
Pressing
When the grapes are gathered, they are transported to the pressing machines. After
they have been harvested the grapes are pressed. Each specific grape (black, white and others)
are pressured independently. For the appellation Champagne, all the grapes must be unbroken
and entire when they are setted down on the wine-press.
Whole grapes are loaded gently into enormous presses and, slowly, the juice is
extracted. This occurs three or four times and each time more tannin and colour comes out of
the skins, although the actual skins and pulp have to be removed.
The productivity is limited by the rate of rape which is 102 l of rape for 160 kg of
pressured grapes.
The wine press must satisfy some criteria specific of the champagne production:



The loading must be easy, fast and with a short fall of the grapes
The area of pressuring must be large
The juice must be extracted at 90° from the pressure axe to grant rape auto filtration
Five different kind of wine-press are used in Champagne region:

The traditional vertical wine press (before 1950)
o Load capacity : 2000-4000 kg
o Manual maintenance
o Producer : Coquard, Darc, Dol-lat et Marmonier
3




The mechanical horizontal wine press (1950)
o Manual intervention limited
o Load capacity : 2000-12000 kg
The pneumatic horizontal wine press (1950)
o Load capacity : 6000 kg
o Use pneumatic energy
The pneumatic horizontal wine press with lateral membrane
o Use very easy
o Load capacity : 2000-12000 kg
o One of the most used in Champagne production
o Producer : Bücher, Diemme, Jouglet, Mazancourt, Péra, Siprem et Willmes
The hydraulic horizontal wine press (1985)
o Load capacity : 2000-8000 kg
o Entirely automatic
o Still expensive
o Producer : Coquard
First Fermentation
Before the fermentation, the acidity of the grapes juice must be controlled to
insure a good ageing process.
Fermentation takes place in stainless steel cylinders or barrels; where yeast is added to
the grape juice so fermentation can occurs. Separate blocks are kept for each vineyard. The
yeast feeds on the sugar in the grape juice and releases alcohol (as ethanol), heat and carbon
dioxide. In this first fermentation, the CO2 is not important, so it is released via valves in the
tanks.
This first fermentation is called alcoholic fermentation.
C6 H12 O6 + yeast ---------> 2 C2 H5 OH + 2 CO2 + Q
What are the chemical changes occurring in fermentation?
The sugar is present in the grape juice as glucose, C6H12O6, which is converted to
pyruvate during a long and complicated biochemical pathway called glycolysis. In normal,
4
aerobic conditions the pyruvate is converted into a form that can be used by the cell to give
energy via two more pathways, the citric acid cycle and the electron transfer reaction. Under
the anaerobic conditions found in the wine bottle, the pyruvate is then converted by the yeast
to ethanol.
This is a two-step reaction:
(1)
The pyruvate decarboxylated to acataldahyde, releasing CO2 gas.
This is catalysed by the enzyme pyruvate decarboxylase.
(2)
The acetaldehyde is now reduced to produce ethanol. The H+ comes
from NADH, a naturally occuring electron carrier. This is a
reversible reaction and is catalysed by the enzyme alcohol
dehydrogenase in the fowards direction.
5
Blending
From each of the fermented batches of wine a small sample is taken and tasted by the
wine makers. The selected samples are then taken and combined to give a final master blend,
which is called the cuvée. This can be a very difficult process since it requires the wine
makers to predict the final flavour of the blend after the second fermentation.
The remaining blocks of wine that have not been used in blending are auctioned off to other
vineyards.
Bottling, Second Fermentation and Ageing
Sugar and yeast are added to the final blend to induce a second fermentation.
This second fermentation is called the malolactic fermentation:
(COOH)² - CH2 - CHOH --------> CO2 + CH3 - CHOH – COOH
This wine is then bottled and capped in the bottles that will end up on the shelves of
the wine seller. During the second fermentation the yeast increases the level of alcohol and
adds CO2 which creates the bubbles in sparkling wine. This process takes about four to eight
weeks. The yeast must now remain in the bottle for at least a year to allow the champagne to
age, even though the fermentation process is complete. The bottles rest horizontally on top of
each other where the yeast collects along the bottom side. Most producers allow the sparkling
wine to age for three to seven years before uncorking and removing the left over yeast. The
alcohol content of the wine is limited because at a certain concentration the yeast becomes
"drunk" and can no longer ferment.
6
Riddling
Once the wine has aged, there's still the task of removing the yeast from the bottle. An
ingenious method called riddling is employed. The bottles are placed at a 45 degree angle in
either an automated or manual turning rack. Then the bottles are periodically rotated. This
process forces the yeast down into the cap of the bottle. The mechanical riddler can achieve
this in about a week, while the manual riddler takes about one month.
In the Champagne region, four machines are principally used to riddle:

The Champarex :
o Capacity = 183 or 381 bottles
o Hexagonal metallic container
o Manual rotation of the container
7



The Pupimatic
The Rotopal :
o Capacity = 297 bottles
o Metallic container
o Manual rotation of the container
The Gyro :
o Capacity = 504 bottles
o Automatic rotation
o Very short cycle of riddling
Disgorging
After riddling the yeast is ready to be removed. In former times it was done manually.
When the CO2 bubble arrived in the neck of the bottle, somebody used a claw to
remove the metallic capsule. The yeast was also expulsed with the gas.
Now the tops of the bottles are frozen, trapping the yeast as an ice plug in the cap
which prevents it from falling back into the sparkling wine. A disgorging machine removes
the cap from the bottle and the pressure built up inside shoots out the yeast ice plug.
8
Dosage
This final stage before corking and wiring allows the wine maker to adjust the blend.
Generally a combination of sugar and wine will be added to balance the high acidity of the
dry wine. The amount of sugar added determines the designation on the label: non-dosée,
brut, extra sec, sec, demi-sec or doux, in ascending order of sweetness. Sulphur compounds
can also be added to help preserve the wine. Finally, the cork is forced into the bottle and
capped with a wire hood.
Chemical Additives to Wine
Small amounts of sulphur compounds, usually sulphur dioxide and sorbic acid, are
often added to the finished wine to help prevent spoilage by micro-organisms while the wine
is maturing. Sorbic acid was originally obtained from the berries of the mountain ash tree and
has been produced commercially since 1954.
A small amount (about 0.001%) of sulphur dioxide, SO2, is effective in inhibiting the
growth of bacteria. This is usually added as sulphite, but is not an effective fungicide. Sorbic
acid (trans,trans-2,4-hexadienoic acid) is a good fungicide but is not much use as an
antibacterial agent; hence when added together the two are very complimentary.
The last process is the corking. Then the bottles need to be “dressed” with their tags. The
following step of the champagne making is the selling which is specified for each producer in
Champagne region.
9