Each year,
our partner
winemakers work flat out for several weeks during the harvest.
It's the most stressful time of the year for them, and as the
participants of the Gourmet Odyssey
Harvest Experience
Days have learned, their work is far from over once the grapes
have been picked. Their skill, knowledge and experience are
immediately called upon in the cellar to ensure that the juice from
the grapes produces a good wine!
So what are the secrets of the cellar once the harvest has been
sorted and put into the vats? It depends on the type of wine
being produced. At our partner
winemakers, they produce mainly white and red wines.
White or red wine?
As we saw in the article describing the harvest,
many of the harvested bunches of grapes for making red wine are
sorted and de-stemmed to separate the grapes from the stalks.
Sometimes the winemakers will then decide to lightly crush the
berries. In the olden days this was done by foot or by hand, but
these techniques are now much rarer because the machines that
de-stem the grapes can also be used for this purpose. The aim of
this step is to break the grape skins and to help diffuse the
tannins and colour during the maceration period to follow. For
the white wines, the grape bunches are generally put in whole,
directly into the press.
The next steps differ depending on whether red or white wine is
being made. For red wine, we put the must, containing all of the
matter that makes up a grape (the skin, flesh, juice and pips),
into a vat or cask to start fermenting. The contact between the
juice and other components of the berry during the maceration
period will help to develop the colour and taste of the wine. To
make white wine, the grapes are pressed as soon as they have been
harvested so as to extract the juice from the elements which
could colour or make the wine tannic.
Pressing is a very important but delicate step for making white
wine, as the winemaker needs to find the right balance between
pressing the grapes sufficiently hard to extract as much juice as
possible, and not over pressing them which can give grassy and
acidic tastes. Once the juice has run off, the must is left alone
so that the tiny solid particles that have been carried into the
vat settle at the bottom. This is known as clarification or
débourbage.
The alcoholic fermentation
Whether it's the juice to make red wine that is macerating in the
vat, or the juice to make white wine that has been pressed, the
moment will come when the sugar that it contains will start to
turn into alcohol. This is known as the first or alcoholic
fermentation. It usually starts all by itself thanks to the yeast
found naturally in the must. It can also be set in motion by
adding selected yeast or some must from another vat that has
already started to ferment.
The temperature during the fermentation period is crucial and
differs between white and red wine. In both cases, the yeast
stops working below 10°C and the cells die above 35°C. The
winemakers can control the temperature of the vats by pumping hot
or cold water into an immersion heater or around the jacket of
the vat. For red wines, fermentation generally takes place
between 25 and 30°C to keep the maximum aromatic properties
whilst extracting the tannins and colour. For white wines, the
temperatures can be kept lower, between 15 and 20°C because no
extraction is needed, allowing more aromas to be kept. The
alcoholic fermentation usually lasts anywhere between a couple of
days and a month.
There is another peculiarity for the red wines. As the
fermentation takes place, carbon dioxide is released, which
pushes the pips, skin and any other solid matter to the top of
the vat, causing a cap to form. The colour and tannins necessary
for the wine are contained within this solid matter, but the
juice stays below the cap. It?s therefore necessary to keep the
juice in contact with it by punching the cap down into the juice
(pigeage), or by drawing off the juice from the bottom of the
vat, pumping it to the top and letting it filter down through the
cap (remontage). Depending on the style of wine that the
winemaker is hoping to achieve, this will be done for each vat
anywhere between a couple of times a day to once every few days.
The malo-lactic fermentation
Once the juice has been transformed into wine, more patience and
work is needed whilst it ages. Generally, once the first
fermentation has finished, the winemaker will rack the wines to
separate them from the larger lee particles and put the wine into
a clean vat or into barrels.
For red wines, when the wine from the fermentation tank is drawn
off, we get what is called free-run wine (vin de goutte). The
remaining marc of solid² matter is then pressed to extract the
rest of the wine, which is known as press wine. These two wines
are then either blended together during the ageing period or are
aged separately, leaving the winemaker the choice to blend them
or not at a later stage.
Shortly after alcoholic fermentation, a second fermentation
starts, the malo-lactic fermentation, which transforms the malic
acid into lactic acid. This decreases the acidity and softens the
wines, so is also an important step in making good quality wine.
Then comes the magic of the winemaker in ageing the wine. Each
has their own methods and preferences concerning the container
used (concrete or stainless steel vat, wooden cask, old or new
barrels etc), the length of time needed for ageing, the blend,
and so on. As our partner
winemakers often remind us, it's as much about personal taste
as anything else, and so they task themselves with the onerous
job of regularly tasting all of their wines throughout the ageing
process!
To learn more about the vinfication, ageing and blending of wine,
why not join us for a Gourmet Odyssey Vinification
Experience Day!
Other articles relating to the 2015 vintage
The 2015 harvest gets under way for our partner wineries