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Wine (the beverage) FAQ, part2 of 10 [LONG]

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Archive-name: drink/wine-faq/part2
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I.  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 befermentation, that is,
thatsugar 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. 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 wine") are the most "natural." Both
table and sparkling wines tend to have alcohol contents between 7 and 15
percent.
 _
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II.  HOW WINE IS MADE
 

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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."



Growing Grapes:  Phylloxera vastratrix
 

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


Growing Grapes:  University of California at Davis_
 
To some, scientific saviours, to others, an institution that caused severe
problems in the California wine industry. To all, it is clear that the
University of California at Davis (UCD) runs a highly-regarded enological
program which has brought modern science and technology into the process
of making wine. Find their excellent web site
[http://wineserver.ucdavis.edu/] at http://wineserver.ucdavis.edu/. 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, it is said,
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!
 
Why did the debate about Davis come about and why it is so volatile? What
follows is a rough 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!
 
-------------------------

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 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."

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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 not 20 miles away, 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.


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 . . . .

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 sulfiteswhich
remain in the wine may cause a lot of discomfort to some wine drinkers
(see the section on _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 commented 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 place to mention "Brett" or the Brettanomyces strain of
yeast. But since it is a side-light and this is written as a hyper-text
document, you can check it out now. Otherwise, you will find the
discussion as the next section.
 
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 steelcontainers 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.
From Fermentation to Bottle:
 
Malolactic, Filtering and Fining, Barrel Aging and Blending
 ---------------------------------------------------------------------------

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.
 
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 cheese-cloth, 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 gelatinor 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."
 
The winery may then keep the wine so that there can be additional
clarification and, in some wines, to give it a more complex flavor. Flavor
can come from wood (or more correctly from the chemicals that make up the
wood and are taken up into the wine). When wood aging is used, wines are
stored most commonly in oak barrels. It it is considered by many that
French oak barrels give the best flavor and that they must be replaced
after several years of use. American oak is used by some producers and you
can usually tell the difference. Other producers will buy the older, used
French oak barrels and create wines that some feel are inferior (but they
probably _are_ less expensive). Some wines may never see anything but
stainless steel and the glass that they are bottled in. In any event,
using oak barrels puts an "oakiness" characteristic in wine. The wine may
be barrel aged for several months to several years.
 
Ignoring any additional processing that might be used, you could empty the
barrels into bottles and sell your wine. However, during the barrel aging,
the smaller containers may develop differences. So the winemaker will
probably "blend" wine from different barrels, to achieve a uniform result.
Also, the winemaker may blend together different grape varieties to
achieve desire characteristics. For example, blending a little Merlot into
a Cabernet Sauvignon can give is a more "mellow" taste. This process also
temporarily creates very purple stained teeth in the red wine maker. Other
blends may seem unusual. Recently I had a blend of 50% each Chardonnay and
Viognier. (I liked it.)


Bottling Wine
 ---------------------------------------------------------------------------


At some point the wine will be placed in bottles. Producers often use
different shaped bottles to denote different types of wine. Colored
bottles help to reduce damage by light. (Light assists in oxidation and
breakdown of the wine into chemicals, such as mercaptan, which are
undesirable.)
 
Bottle sizes can also vary:
 
_Applying generally to wines other than Champagne_
 
Split ------------------------------------------- 187.5 ml
Half bottle ------------------------------------- 375 ml aka Fillette)
Bottle  ----------------------------------------- 750 ml
Magnum  ----------------------------------------- 1.5 liter (2 bottles)
Marie-Jeanne -------------------- 2.25 liters (3 bottles) (Red Bordeaux)
Double Magnum ----------------------------------- 3 liters (4 bottles)
Jeroboam ---------------------------------------- 4.5 liters (6 bottles)
Imperial ---------------------------------------- 6 liters (8 bottles)
 
_Applying to Champagne bottles_
 
 Split --------------------------------------------------- 200 ml
 Half bottle --------------------------------------------- 375 ml
 Pint ---------------------------------------------------- 400 ml
 Bottle -------------------------------------------------- 800 ml
 Magnum  -------------------------------------  1.5 liter  (2 bottles)
 Jeroboam ------------------------- 3 liters (4 bottles) (& Burgundy)
 Rehoboam ------------------------- 4.5 liters (6 bottles) (& Burgundy)
 Methuselah ----------------------- 6 liters   (8 bottles) (& Burgundy)
 Salmanazar ----------------------- 9 liters   (12 bottles)
 Balthazar ------------------------ 12 liters  (16 bottles)
 Nebuchadnezzar ------------------- 15 liters    (20
bottles)
 
_And also:_
 
A _case_ is 12 bottles or 24 "half" bottles.
 
Just prior to filling the bottle, the producer may insert nitrogen, which
will sit above the liquid preventing contamination by oxygen. A capsule
will be placed over the top of the bottle. Originally made from lead foil,
fears of lead poisoning (and U.S. law) have brought about the use of other
metals, plastic, or even nothing at all.
 
--
 

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