When is a
wine 'fault' not a wine fault?
By Nick Alabaster
A popular misconception is that Dom Perignon, a monk from
France, invented Champagne. However, while he’s rightly credited
with its ‘discovery’ and analysis, he actually spent much of his
time trying to correct what was considered a fault! It is believed
that the British realised that in fact the fault had a positive side,
and at this point the trait was established as a legitimate wine
style. Today, either a wine is created deliberately with secondary
fermentation (or bottle re-fermentation) - the Champagne method - or
if it occurs accidentally, it is considered to be a fault.
This is just one example of many features of wine that can be
considered either a positive or negative trait, depending on the
unlike the example outlined above, with most ‘faults’ it is often
not so easy to state with complete authority that they are good or
bad. As I will now try to outline, it often comes down to a precise
matter of taste.
Similar myths to Champagne have been around concerning the
creation of dessert wines affected by ‘noble rot’ (Botrytis cinerea).
It is easy to imagine that there was a time when all grape rot
was considered bad. At
some point, though, someone stumbled on the discovery that a
particular type of rot, quite common long after the grapes would
ordinarily be considered ripe and during the cool damp days of autumn,
created a luscious, rich, sweet styled of wine which many people would
enjoy. At this point it
would become a conscious decision of the winemaker as to whether to
encourage this kind of rot or not.
However, what happens if this kind of rot affects a wine –
even when the winemaker didn’t deliberately aim for such a style?
Is it then good or bad? As
in most of these cases: it depends. It is possible to come across such
wines, which have a botrytis-affected streak in them.
Nowadays, with a popular move towards a riper styled wine, late
season rot will likely play a role in either enhancing or spoiling a
wine’s style. More
often than not, the drinker of a wine will not know if a wine contains
noble rot affected grapes, and simply makes their impression based on
the overall wine. Even
more so, under and over-ripeness of grapes makes a huge difference to
the style of a wine, and these more general features of a wine can
also be seen in a positive or negative light.
‘Over-ripeness’ and ‘under-ripeness’ tend to indicate
ripeness levels away from the ideal. However, many wine makers strive
for a level of ripeness which is very difficult to attain
consistently. The result could be an under- or over-ripe style, either
fairly consistently and deliberately, or simply determined by the
year’s weather conditions. But would this always be considered bad,
even if not deliberate? Certainly
not, but it’s likely that the more than you move away what would be
considered the ‘ideal’ ripeness (if such a concept really exists),
the more likely you are to split the table between admiration and
What it often comes down to is a matter of subjective taste.
My personal tastes err towards to under-ripe style. Leafy
cabernet fruit, rather than porty, jam-like flavours. Hints of
vegetable and undergrowth (especially rhubarb which I really find
attractive) rather than prune and tar in my shiraz and so on. But that
is exactly what it is – my personal taste. These ripeness levels are
often matched by variation in alcohol levels, which also give yet
another feature which may or may not be within expectations for what
is considered right or wrong for the style.
The substance in the bottle which we call wine is in fact an
incredibly complex liquid. One
thing it is not is simply crushed grape juice. The sugars natural in
grapes lead to their fermentation, where yeasts convert the sugars to
alcohol. Yet it is also these yeasts, and bacteria too, which lead to
incredibly complex reactions and chemical changes which create a
diverse range of by products forming the characteristics of wine. Many
of these chemicals and organisms impact the wine at various points in
its creation. However, I shall concentrate on just a few which clearly
show how difficult it is to say when a ‘fault’ is really a fault.
Volatile acidity (VA) is caused by naturally occurring
chemicals in wine, produced by the actions of acetic bacteria.
It can be shown that there are measurable levels of VA in all
wine. VA is split between two types of chemical – acetic acid and
ethyl acetate. Rightly or
wrongly, I tend to think of the acetic acid affecting the taste with
the sourness or edge to a wine which recalls vinegar, with the ethyl
acetate leading to various volatile traits from a mild ‘lift’ to
the nose which isn’t directly noticeable, through a boot polish kind
of aroma, to nail varnish remover in the worst cases.
The fact is that acetic acid and ethyl acetate are formed
together and such a distinction may not in fact be so straightforward.
But then that’s wine for you – it is more than likely that
a complex picture of elements are involved in whether we perceive an
issue or not. In the case of VA, it’s not just the level – but also the
wine style and type. The
richer, bigger wines (Port, for example) can carry greater amounts of
VA without detriment. In
fact, the sweet dessert wines styles affected by noble rot actually
seem to need high levels of VA in order to help form the nose.
Without these more volatile elements, the heavy, sugary wine
would not give much on the nose at all, and the VA provides an
essential ‘lift’ to bring the less volatile elements to our nose.
Our nose of course is also a large factor in our perception
between good and bad. Some people will be more sensitive to certain
chemical than others. I
often perceive fault with a lower level of VA than others, but even
that can change with my mood and I can honestly say that my general
acceptance level is not consistent.
So what determines when VA is a fault or not? You could say
when you notice it but that isn’t often the case.
Sometimes the edge is not detracting amongst all the other
aromas a wine offers, and in many cases it provides a positive
element. Sometimes you
may not appreciate that a winemaker has aimed for a certain level of
VA, so what may be a deliberate trait may also be considered positive
or negative depending on personal judgement.
You certainly can’t simply measure levels to distinguish good
from bad without taking into consideration the effect on the whole.
However, the higher the level the closer you come to a wine pushing
the level to the brink and beyond, into the territory where personal
taste will be the determining factor.
Another form of ‘fault’ is the yeast family known
collectively as Brettanomyces or brett for short.
But to simply write off these yeasts as faulty winemaking would
be to write off many successful styles of wine.
In the modern era we have all the winemaking techniques to
making clean and very fruity styles of wine.
However, it is not these types of wines which people consider
to be the highest form of wine. Alongside the balance, concentration and longevity of a wine,
people consider ‘complexity’ to be a factor in determining the
extraordinary from the ordinary.
While it would be wrong to say brett always, or even often,
plays a part, many famous examples of respected wines contain
measurably levels of chemicals which have come about by the growth of
brett (primarily in the maturation casks, but also in the bottle).
There are generally two or three substances which indicate the
presence of brett, and it is these substances which affect the wines
characteristics. At a very low level, the smoky/spicy side of brett may be
displayed. Perhaps more
indirectly noticeable at low levels is the impact on the overt
fruitiness of a wine. What
brett can do is take an otherwise fruity wine and balance the fruit
with an earthier style of wine. For
some that would be consider positive, although again it is all a
question of balance and taste. Higher
levels and the wine can on a horsy/animal hair (ranging from horse
saddle to wet dog) like character.
Not for everyone for sure, and it is at this point where the
audience becomes markedly split. Around this level, depending on the wine, brett can make
itself know with an barn/farmyard character, and in fact this trait is
very highly regarded by many. Again, all a question of taste. Higher levels still and the wine takes on a sewage/silage
character – and none but the most extreme element among wine lovers
(or is that most insensitive) can bear to drink such a wine.
To remove brett entirely could be considered positive,
especially as it is difficult to control its spread and development.
But to remove it will also take away some of the positive
non-fruit derived flavours in wine. In fact there are a huge number of
factors contributing non-fruit flavours to wine, and often as not
these are the actions of various yeasts and bacteria in wine, some
deliberate, some not. Many
wines, after the action of yeast fermentation, also then undertake a
controlled and deliberate bacterial transformation.
Harder malo acids are converted to softer lactic acid in the
process, which is known as malolactic fermentation.
The bacterial inoculum in this case is usually a specially
cultured product and the wine will seem softer, more rounded as a
result. However, one of
the ‘accidental’ bacteria in wine is Lactobacillus. This
can live off any remaining sugar in a wine and also creates lactic
acid. This can also help soften a wines fruity character – add a
savoury edge (quite possibly a certain meaty character also) to a wine
– which is often considered positive.
However, it can go too far and the wine can turn sour like
spoilt milk. Controlling
such an infection is not possible once it starts, and shows how a
winemaker walks a tightrope with a natural product, full of natural
food supplies and a ready army of organisms ready to feed on them
given the chance. Sometimes
the result will be positive, and other times not.
Luck does indeed play part of its final impression, as does the
individual tastes of the person drinking the end product.
Finally, I leave you with thoughts about wine maturity.
Some wine styles use oxidation in a positive aid to their
development, and others need an oxygen free environment or a
combination to develop positively. My personal preference is not to
find bottle oxidation playing a role, but others relish the nutty,
leathery, decaying tone that it brings.
However, it is a far from uniform process (no thanks to natural
corks, but also contributed to by storage and bottle variation), and
it is often a combination of factors which makes up a wine’s
development profile. What the drinker is left with is simply the
decision: do they like the result or not?
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