Wine Production : Vine to Bottle - Vinum Vine

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WINE PRODUCTION
of rainwater per hour. It is interesting that the authorities do not
consider that this negates the concept of terroir, but when two
Bordeaux properties covered their vineyards with plastic sheeting
during the 2000 growing season, the resulting wines were not accepted
as AC (resulting in the world’s most expensive Vins de Table).
During the fermentation of red wine, the maker may decide to ‘bleed’
the vats, by running off some juice, leaving behind a reduced quantity
to continue the maceration on the grape skins and concentrate
flavours. Oxygenation of the fermenting musts will help soften tannins,
which may be very hard in less sunny years, and also reduce ‘green’
flavours. The length of post-fermentation macerations on the skins
will also be reduced in such years in order to balance the tannins
with the level of fruit.
16.4 Problems in winemaking
It is obvious that to make top quality wine, the grapes must be fully ripe
and disease free. However, during the winemaking process, quality
can be lost at any and every stage of the process. We will consider
just a few potential causes of quality loss below.
16.4.1 Delay in processing fruit
Grapes should be processed as soon as they are harvested. Ideally,
the fruit should be transported in small containers, so it does not
crush itself under its own weight. The longer the grapes are left
waiting before they are processed, the more risk there is of bacterial
spoilage or oxidation. This is particularly important in a hot climate,
where the process of deterioration is much faster than in a cool
climate.
16.4.2 Lack of fruit selection
Even if the fruit is basically ripe and disease free, invariably there
will be some rotten or otherwise poor grapes arriving at the winery.
Inspection and elimination of unwanted grapes or materials other
than grape is necessary to ensure good wine. In countries where