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WINE MAKING |
In the winery the winter activity
is of course wine-making. This combination of science, craft and a sprinkling
of good luck is the crucial operation which turns the humble grape into
something people like Oz Clarke can wax lyrical over. So, what is involved...? The
first requirement is of course good disease-free grapes, as ripe as possible,
and most importantly having the correct acidity at the time of picking. In the
right hands the very best grapes will make the very best wine. That is not to
say they will taste the nicest - indeed some fabulously expensive wines such as
the German sweet dessert Trockenbeerenauslese are made from grapes that are
virtually uneatable. In England we have to reconcile ourselves to the fact that
we are too far north to get really ripe grapes as a normal crop. However
provided we use vines developed for cool climates, and restrict ourselves to
making suitable wine styles (mainly white, light and dryish still or sparkling
types) we can make wines the equal of any in the world. Heavier reds and whites
need more ripeness obtained from a longer summer season, and are only made in
England with some difficulty.
It is the development over a long
season that gives the grape its unique wine-making properties. From flower to
harvest is typically 14-15 weeks, which enables the fruit to achieve very high
sugar contents, and pick up all sorts of interesting flavours which increase
the complexity of the final wine. Once the grapes have been picked and pressed
we add a small amount of pectolitic enzyme to help clear the juice (or `must'
as it is called at this stage). After 24 hours we rack the must (draw the clear
liquid off any sediment), add yeast and a fermentation aid such as diammonium
phosphate, and away it goes.
The fermentation typically takes 2-6
weeks, after which we allow the wine to settle. We try to extend the
fermentation for as long as possible as a slow rate retains the more fragile
aromatic components which will later give the wine its beautiful 'bouquet' or
'nose'. The fermentation generates heat which increases the fermentation speed,
and here the English climate works in our favour because the cooler conditions
at this time of the year slow the fermentation down without having to resort to
cooling the vessels. It is very important to maintain strict cleanliness at all
times, and as much as possible exclude air to prevent oxidation - we keep the
tanks full and cover the wine with carbon dioxide. The yeast, having done its
job, falls to the bottom of the tank to form a layer called the `lees', and the
next stage is to rack the wine from above the lees. We then add finings of
bentonite (a natural clay material) to aid settling, and filter and bottle the
wine. This then is the basic process - familiar to all home wine-makers. Beyond
this though there are many other small adjustments we can make to the wine to
improve it. For example we can reduce the acidity, add sugar in legally limited
quantities to increase the alcohol content (generally the increase is limited
to a maximum of 3.5% alcohol), or impart oak flavouring either by using barrels
or chippings. Our little laboratory is backed by specialist companies with very
sophisticated (and expensive) facilities
Tasting the wine during making is
very important, but by itself it is not enough. It must be backed up by
chemical analysis. To give some idea of the complexities let us look at some of
the processes involved:
·
At harvest
we need a particular acidity in the grapes - around 9gm/litre for still wine,
and 10.5gm/litre for sparkling - expressed as equivalent to tartaric acid and
determined by titration. Most wine-makers could not tell the difference between
these two accurately by taste, yet it is crucial. During ripening the acid may
only be at the correct level for a few days. This is where blending comes in -
we have used the 11 different white grape varieties in our vineyard to produce
the best possible juice (or "must" as it is called).
·
Next there
is sugar level. For most dry white wines we aim to produce about 11 to 11.5%
alcohol, but for the sparkling it is lower (around 10.5%) as there will be a
second fermentation giving about another 1.5%. The measurement is fairly easy
to make using a hydrometer and standard tables.
·
The use of
sulphur as a de-oxidant is very important, but the concentration must be
correct, and accurate analysis is essential.
·
Removal of
proteins is essential, and we use finings of Bentonite (a naturally occurring
clay), but the amount must be correct - not enough and the wine will be
unstable and cloudy, but too much will rob it of flavour and smell. We do a
test for this.
·
Then there
are all the more complex features of the grape which come into play - such as
whether it is neutral or aromatic in character. Will the flavour be improved by
oak? Should the malic acid be converted to lactic acid by a process known as
malo-lactic fermentation? This is where tasting reigns supreme!
|We get complex analyses carried
out by a specialist laboratory, and a full analysis (costing about £50) is
required for most competitions. Even professional judges can be fooled, and a
wine with too much sweetness (for instance) to be classified as dry would have
an unfair advantage if entered in that category in a competition.
The wine lies in the bottles in our insulated
wine store for at least a few months to develop its full character. During this
time we keep it in the dark, and as free as possible from temperature changes.
English wine does not really need to be laid down over years like some full
bodied Clarets or Sauternes, but it does need some time to mature. This can
vary from 2 -3 months to perhaps a year or so. After this the wine will not
really improve, but it shouldn't deteriorate for some years. However we prefer
you not to keep it long, but drink it quickly and come back for some more!
Once we have made the decision to sell the
wine we rinse off the outside of the bottles and label and box them. We hold
only a minimum stock of boxed wine because it takes much more space to store
boxed than in a bottle stack or 500 - 700 bottle crates. Also the temperature
keeps more stable in a large stack.