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

This article was archived around: 30 Sep 2000 17:19:40 GMT

All FAQs in Directory: drink/wine-faq
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Archive-name: drink/wine-faq/part2 Posting-Frequency: monthly Copyright: (c) 1995-2000 Bradford S. Brown (Notices/Disclaimers in pt. 10) Last-modified: 2000/06/01 U.S. WWW (HTML) Mirror: http://www.sbwines.com/usenet_winefaq [newest] U.K. WWW (HTML) Mirror: http://www.bath.ac.uk/~su3ws/wine-faq/wine-faq.html
Note: This ASCII version was created by "washing" the WWW HTML version through WEB2TEXT. This freeware is available from Damien Burke at http://www.jetman.demon.co.uk/software/index.html This might lead to some interesting or odd formatting, since it has to figure out just what was being done in the HTML version. For example, bold text usually comes out with an underscore on either side, e.g., _this is bold_ . There may be other things, but generally speaking, it does a good job! --------------------------------------------------------------------------- I. WHAT IS WINE? --------------------------------------------------------------------------- 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. _ --------------------------------------------------------------------------- II. HOW WINE IS MADE --------------------------------------------------------------------------- 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 --------------------------------------------------------------------------- _ 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." ------------------------------------------------------------------------------ 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. --