Archive-name: wine-faq/part3
Posting-Frequency: monthly
Copyright: (c) 1995 Bradford S. Brown (see Notices & Disclaimers in pt. 10)
Last-modified: 1996/07/26

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*1. WHAT IS WINE?
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Wine is fermented grape juice.  That's the standard answer.
Actually, wine can be made from all sorts of common and not so
common foods.  Things like fruits, herbs and flowers.  Most wine,
though, is made from grapes.  And no matter what the wine is made
from, there must be fermentation, that is, that sugar be
transformed into alcohol.  If the amount of alcohol is relatively
low, the result is wine.  If it is high, the result is a
"distilled liquor," something like gin or vodka.  Or perhaps the
ever popular 151 rum ("flammable, use with caution").

By the way, as fermentation cannot increase alcohol content past
about 16%, for at that level the yeast dies and ends
fermentation.  Higher alcohol levels are archived through
"distillation" (that is a lower alcohol beverage is heated.
Alcohol, evaporating first, is collected and the vapor re-
condensed).

There are red wines, pink wines (also known as "rose" or
sometimes "blush") and white wines.  By the way, since the inside
of a grape is more or less "white," red grapes can make white
wine.  The color comes from letting the juice mix with the skins
during the early wine-making process.  A good example of this is
White Zinfandel.  The Zinfandel grape is very red on the outside.
So, red grapes can make white wine, but white grapes can't make
red wine.

Wines might be "fortified," "sparkling," or "table."  In
fortified wines, brandy is added to make the alcohol content
higher (around 16 to 23 percent).  Sparkling wines are the ones
with bubbles, like Champagne.  Table wine (which can also be
called "still") are the most "natural."  Both table and sparkling
wines tend to have alcohol contents between 7 and 15 percent.



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*2. HOW IS WINE MADE?
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*2.1 GROWING GRAPES

Grapes grow on vines.  There are many different types of grapes,
but the best wine grape is the European Vitis vinifera.  It is
considered optimal because it has the right balance of sugar and
acid to create a good fermented wine without the addition of
sugar or water.  It has been said that the wine is only as good
as the grape; a poor winemaker can ruin good grapes, but a good
winemaker isn't going to make great wine from inferior grapes.

Now before I say anything else about grapes, let me point out an
error I have made in drafts of this document (and for all I know
it may persist--proofreading is an art).  That is the difference
between "varieties" of grapes and "varietals."  The word
"varietal" means "of or pertaining to a variety."  Types of
grapes are "varieties."  Wines made from a single variety are
varietal wines.  So, for example, a 100% Cabernet Sauvignon wine
is a varietal.  The cabernet sauvignon grape, zinfandel grape and
merlot grape are varieties of grapes.  (Of course, don't be
confused that, for example, United States law allows a wine to be
labeled Cabernet Sauvignon so long as it has at least 75% of that
variety of grape.  Now, is that clear?)

Vines start producing grapes about three years after planting; a
useable crop after five years.  They reach their prime in terms
of crop yield between ages ten and thirty.  Vines can grow for a
hundred years, though production is reduced as they get older.
However, reduced production (which is also caused in other ways--
growing in poor soil, lack of irrigation, pruning the vines,
climate, etc., the so-called "stressing the vines") can lead to
"better" wine.  So some very good wines come from "old vines."

Wine has been around for thousands of years, but in 1863,
catastrophe struck.  French vineyards were infested by
Phylloxera.

*2.1.1 Phylloxera vastratrix

Phylloxera is a louse that attacks the roots of the grape,
causing the leaves to fall off and eventual death of the plant.
The bug had come from America where the grapes were resistant to
the creature.  Phylloxera spread quickly through much of Europe
and would have been completely devastating, except that a "cure"
was found.  It was possible to take Vitis vinifera and "graft" it
to American rootstock.  The American rootstock was not affected
by phylloxera and the grafted grapes were the European variety.

French grapes grow well in soil rich in lime.  Native American
grapes don't (and the wine they make is derogatorily described as
"earthy" or "foxy").  American grapes were resistant to
Phylloxera, the French grapes were not.  Why not create a
"hybrid" that has the best qualities of both?  (You could grow
the grapes from the hybrid, and this is done is some parts of the
world, however most graft the desired variety of European grape
onto the hybrid rootstock.)

There are many hybrids, but for California wineries, one
particular hybrid rootstock seemed to stand out among all the
rest:  AxR #1.  During the 1960's, wine grape planting in
California took off.  (Some farmers in the Napa valley saw their
relatively inexpensive land soar to US $50,000 or so an acre.
It's interesting to see the old farmhouses with the shiny new
Mercedes parked in front of the homes of the luckier farmers--and
no, I don't think all the Mercedes belong to transplanted doctors
and lawyers.)  AxR #1 was planted all over the place.

Unfortunately, it turned out that there were at least two types
of Phylloxera, known as Biotype A and Biotype B.  AxR #1 was
resistant to the first, but not the second.  Type B is now
spreading like crazy throughout the state.  While there are other
rootstocks to chose from, many producers may not be able to
withstand the cost of replanting and will close.  (It takes five
to seven years for new vines to produce grapes--too long to wait
for many.)

The grower makes the decision on what stock to plant, but there
are those who have heaped a fair amount of blame on the people at
the University of California at Davis (UCD) for supposedly
"pushing" AxR #1.  It had been known by the French for at least
50 years that AxR #1 was not perfectly resistant.  It would fail
after 10 or 20 years in the ground.  While AxR #1 has many good
qualities, whether UCD did not make enough of AxR #1's
shortcomings remains a controversial topic.

*2.1.2 University of California at Davis

To some, the devil incarnate, to others, scientific saviours.  To
all, it should be clear that UCD runs a highly-regarded
enological program which has brought modern science and
technology into the process of making wine (WWW address--
http://pubweb.ucdavis.edu/Documents/WINE/ven1.html).  The school,
as was explained to me by a graduate of the program, provides
higher education in enology (wine chemistry) and viticulture
(grape horticulture) and not, specifically, in the art of
winemaking.  Most students opt to pursue careers in the wine
industry and take "Planned Educational Leave" to obtain first
hand experience with a winery.  Nevertheless, some criticize that
the wines created by UCD graduates are all the same, "text-book
chemistry" wines.  They claim the UCD learning experience
produces predictable, "inoffensive" wine (and, for example, shies
away from wild yeast fermentation, a way to make wines with "more
character").  All I can say is that I have had truly magnificent
wines from UCD graduates AND from people who started making wine
in a garage without any formal training at all.  Wine making is
an art, not an exact science.  In the end, it will be the SKILLS,
TASTE and ARTISTIC EXPRESSION of the winemaker that is crucial.
As told to me by the Davis graduate, it is ironic that a great
number of the Davis "bashers" are quite willing to contact the
school whenever they have a problem their "art instinct" can't
solve.  All the arguing hardly matters, if you don't like a
particular wine, vote with your pocketbook!

Being a graduate of the University of California, and because it
is interesting to me, I have asked why the debate about Davis
came about and why it is so volatile.  What follows is a rough,
LONG summary of ONE person's opinion (not my own, as I have no
true knowledge at all, at this point).  Other people in the know,
feel free to contact me with their views!

*2.1.3 A Graduate's Opinion of Davis
From the Repeal of Prohibition through the 1960's, Davis excelled
at bringing modern science and technology into the process of
making wine.  For example, Davis promoted the use of stainless
steel tanks, proper sanitation. controlled temperature
fermentations, and provided a better understanding of malolactic
fermentation.  In short, along with the University of Bordeaux,
UCD led the world in improving wine making and answering all the
straightforward questions.

At the same time the wine boom came to Napa, bringing a number of
new persons (into a formerly family oriented industry) who wanted
answers to the harder questions.  Davis-trained enologists were
trained in a more food-processing approach to winemaking.  No
doubt some of them also went out into their profession with a
"superiority" complex for having "gone to university" when the
apprentice approach had previously been the standard.  It is
probably no surprise that Davis began to get a reputation for
sending out young bucks who didn't know the first thing about the
practical aspects of winemaking.  The result was a backlash
against the University.

Whereas once a Davis degree was a ticket to success (and
certainly Davis graduates occasionally got positions solely due
to their degree, not their abilities) as the industry slowed and
jobs got more difficult to find the Davis degree didn't work the
same magic.  Some winemakers then discovered that they could make
a name by Davis bashing (THEIR wines weren't just COOKBOOK
science, so to speak).  About the same time the continuing crisis
involving AxR #1 (see above) began.

Davis bashers would point to the European traditions and enjoy
reveling in the grand reputation of that tradition and tossing
off names of certain selected great wines from certain selected
great years (and ignoring the fact that the bulk of European wine
tends to be plonk--like U.S. jug wines--and not first growth
Bordeaux).  Some winemakers had great success with the so-called
"wild" fermentations and accused (with some accuracy) Davis of
resisting this method.  However, for every successful "wild"
fermentation which gained notoriety there probably was a poorly
produced wine.

In the end, the science that Davis contributes to the field is a
vital and important factor in the growth of the wine industry.
It can smooth out the rough edges foisted on the winemaker by
variables which are all or part out of his or her control
(weather, pests, soil depletion, etc.).  Innate intuition may
make good or even great wine, but science isn't going to hurt,
especially when the winemaker is open to ALL ideas.

As has been oft stated, a consumers pocket book should make the
judgment.  UCD makes recommendations based upon the best
scientific evidence it can accumulate.  This might run counter to
the anecdotal results of a single winemaker's recollection or to
the idea that a winemaker is an independent iconoclast,
unfettered by "rules."  Free spirits may make good wine, so can
science.

The chemistry of wine is extremely complex and a great deal of
ego is involved on both sides of the Davis debate.  One thing is,
however, certain.  Davis does not dictate winemaking.  Davis is
merely a tool to be used by people who want to make wine.  How
they use that tool is up to them and to their abilities.


*2.2 HARVEST

Weather is a major factor is determining whether a year is going
to be a "good vintage" (or "year").  For example, was there
enough heat during the growing season to lead to enough sugar?
At harvest time, the short term effects of weather are quite
important.  To produce great wine, the fruit should be ripe (but
not overripe), and have a high (but not overly high) sugar
content ("brix"; typically about a 22 brix for table wine).
Think of raisins.  As the fruit dries, the water evaporates.
What is left is the sugary fruit.  If it rains just at the point
the wine grapes are ready, and before the grapes can be
harvested, the additional water will cause the water level to
increase, and the brix will go down.  Not good.  (You might ask,
why not just add some sugar in the wine-making process?  Some do.
Also considered "not good.")

Every year the wine grape grower plays a game of chance and must
decide when to harvest.  Simplistically, if you knew it wasn't
going to rain, you would just test the brix until it was just
right, then harvest.  If you harvest too soon, you will probably
end up getting a wine too low in alcohol content (there won't
have been enough sugar to convert to alcohol).  These wines will
be "thin."  If you delay harvest, there may be too much sugar,
which leads to too low acid content.  This also affects the taste
(and the aging possibilities) of the wine.

During the harvest of 1989 I was in the Napa/Sonoma areas of
California, where there was scattered rain.  Winemakers in the
area were not a happy bunch.  As it turned out, this turned out
to not be a great year "overall."  But, it depends.  In some
areas rain was not a factor, in others it was.  So you can't make
a blanket statement that for ALL wines it was a poor year.


*2.3 INITIAL PROCESSING OF THE GRAPE JUICE

Grapes can (and might still) be crushed by stomping on them with
your feet in a big vat.  But a more practical way is to use a
machine which does the job (and at the same time, removes the
stems).

What you get may or may not get immediately separated.  Skin and
seeds might immediately be removed from the juice.  Separation
may not immediately occur (especially for red wines), since skins
and stems are an important source of "tannins" which affect
wine's taste and maturity through aging.  The skins also
determine the color of the wine (see WHAT IS WINE).

Maceration (the time spent while skins and seeds are left with
the juice) will go on for a few hours or a few weeks.  Pressing
will then occur.  One way to press the grapes is to use a
"bladder press," a large cylindrical container that contains bags
that are inflated and deflated several times, each time gently
squeezing the grapes until all the juice has run free, leaving
behind the rest of the grapes.  You can also separate solids from
juice through the use of a centrifuge.

Aside:  When I first started drinking Chardonnay, my tastes ran
to wines with heavy flavors of oak (introduced in the barrel
aging process by storing in wood barrels).  Then I was lucky
enough to be at the Acacia winery in Sonoma during harvest.  The
friendly people there had me take a wine glass and hold it under
the device that was extracting juice from the grapes.  Fending
off the bees, which were very attracted to the sweet fluid, I got
a taste of absolutely fresh unfermented Chardonnay grape juice.
It was wonderful.  I then knew what Chardonnay actually tasted
like!  From that point on my tastes have run to a different
balance of oak and fruit flavors in the wine.  The best way to
learn about wine is to drink it.  Sometimes it even helps if it
isn't even wine yet . . . .


*2.4 TURNING GRAPE JUICE INTO ALCOHOL

Grape juice is turned into alcohol by the process of
"fermentation."  Grapes on the vine are covered with yeast, mold
and bacteria.  By putting grape juice into a container at the
right temperature, yeast will turn the sugar in the juice into
alcohol and carbon dioxide.  The grape juice will have fermented.

Yeast gives flavor to wine.  However things on the outside of a
grape are not necessarily so good for the production of good wine
(for example, acetic bacteria on the grapes can cause the wine to
turn to vinegar).  The winemaker commonly eliminates unwanted
contaminants by using the "universal disinfectant," sulfur
dioxide.  Unfortunately, the sulfites which remain in the wine
may cause a lot of discomfort to some wine drinkers.  (See
ALLERGIC REACTIONS TO WINE.).  Some winemakers prefer NOT to do
this, and purposely create wines that are subject to the vagaries
(and different flavors) of yeast that is "wild," that is not a
commercial yeast strain used by the winemaker ("wild yeast
fermentation").  By the way, some have said that these wild
yeasts are found on the grape, but a number of people have
written to say that there is no documentation that any wild yeast
living on the skins of grapes leads to alcoholic fermentation.
They propose that these "spontaneous" fermentations occur due to
commercial yeast populations that live in the winery and have
become "wild" over several generations--and have not been cleaned
away or otherwise eradicated.

The winemaker has many different yeast strains to choose from
(and can use different strains at different times during the
process).  The most common wine yeast is Saccharomyces.

This is a good point to stop and mention "Brett," also known as
the Brettanomyces strain of yeast (which can be added or come
from wild yeast fermentation).  Found in some beers, it is
considered by some (especially in California) to be almost
completely undesirable in wine.  (Some say it is linked to
development of 4-ethylphenol.)  Mostly this depends on your
taste, it certainly IS found in some French wine (but is never
good in excess).  Look for meaty/gamy/smoky/sweaty socks or
perhaps metallic notes.

That's the short answer about Brett, but the fact is that this is
one of the more controversial discussions for it brings into play
several favorite areas of contention--The University of
California and the idea of just what is winemaking, art, science
or what?

A little (but not a lot) of Brett can let a wine become
distinctly individual.  Somehow, however, it seems that many
California vintners consider any Brett at all a major flaw.
Naysayers like to say that this is due to the influence of the
University of California at Davis (UCD) which, they say, somehow
causes their students to produce standardized "cookie-cutter"
wine.  Brett is definitely found is some French wines, especially
Burgundies and some Rhone wines.  Nevertheless, finding Brett for
some is a major problem--even a defect making the wine unworthy
of purchase.

For some reason whether or not Brett can be found in a wine has
generated a huge amount of cyber-rattling.  (Could I have just
invented a phrase?)  That finding Brett in a wine is a "problem"
that taints a winery (and, I guess, for that reason only gives
them something to talk about).  The more down-to-earth wine
enthusiasts merely say they don't care where the taste comes
from:  if they like it, fine, if not, don't drink it.  Whether or
not something is a "problem" is very much a matter of individual
taste.

To eliminate Brett does mean that any of the characteristics it
imparts will also not be present.  Does this make the wine less
interesting?  Does it make the winemaker less individualistic?
Since, in the end, you can find the wine of your choosing in all
the varieties produced both in California and world-wide, why not
just vote with taste buds and pocket book?

One more thing about "wild yeast fermentation."  The process
gives the "aura" of a hand-craft product.  It is important to
remember that not ALL hand-crafted products are quality products!

Well.  Back to the process. . . .

As yeast works, it causes grape juice ("must") to get hot.  But
if there's too much heat, the yeast won't work.  One modern way
to deal with this is to put the juice into large stainless steel
containers that have refrigeration systems built around the
sides.  The winemaker can regulate temperature precisely.

A less modern, but still wide widely used way to ferment wine is
to place it in small oak barrels.  "Barrel fermentation" is
usually done at a lower temperature in temperature controlled
rooms and takes longer, perhaps around 6 weeks.  The longer
fermentation and use of wood contributes to the flavor (and
usually expense) of the wine.

The skins and pulp which remain in a red wine vat will rise to
and float on top of the juice.  This causes problems (if it dries
out, it's a perfect breeding ground for injurious bacteria), so
the winemaker will push this "cap" back down into the juice,
usually at least twice a day.  In large vats, this is
accomplished by pumping juice from the bottom of the vat over the
top of the cap.  Some winemakers use a screen to keep the cap
submerged at all times.

Eventually the yeast is no longer changing sugar to alcohol
(though different strains of yeast, which can survive in higher
and higher levels of alcohol, can take over and contribute their
own flavor to the wine--as well as converting a bit more sugar to
alcohol).

After all this is completed what you have left is the wine,
"dead" yeast cells, known as "lees and various other substances.


*2.5 MALOLACTIC FERMENTATION

The winemaker may choose to allow a wine to undergo a second
fermentation which occurs due to malic acid in the grape juice.
When malic acid is allowed to break down into carbon dioxide and
lactic acid (thanks to bacteria in the wine), it is known as
"malolactic fermentation," which can impart additional flavor to
the wine.  A "buttery" flavor in some whites is due to this
process.  Since malic acid is perceived as more sour than lactic
acid, the process also reduces the perceived acidity of the wine.

Malolactic fermentation is much more prevalent in red wines than
in whites, with the smell of apples in white wine denoting the
presaging the presence of malic acid.


*2.6 FILTERING AND FINING

After fermentation, there still may be a lot of stuff floating
around in the wine which some winemakers want to remove.  There
are various ways for the wine to undergo this "clarification"
(for example, strain the wine through something like cheesecloth,
called "filtering"), but the most common way is called "fining."

When you make jellies, the recipes may sometimes call for adding
egg whites.  The materials that cloud the jelly are captured by
the egg and you get a nice, bright result that looks really good
in glass jars.  It's the same with wine, even down to using egg
whites.  Except that the most common materials used for fining
are gelatin or bentonite (a type of clay).

When and where to use heavy filtering and fining is highly
controversial, since removing these substances prevents the wine
from obtaining flavors from them, affecting the character of the
wine.  You are certain to hear complaints about "over fined and
filtered wine."  The implication is that such wines will have
less flavor.  For this reason some wines will say on the bottle
that they are "unfiltered."



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