Wine

I

Introduction

Wine, term for an alcoholic drink made by fermenting the juice, in fresh or concentrated form, of fruits or berries. Most wine, however, is made by fermenting the juice of fresh grapes alone, and wine as an unqualified term is commonly understood to meet this secondary definition. The alcoholic strength of wines varies from about 7 per cent alcohol by volume (abv) to about 16 per cent abv; most wines are bottled at between 10 and 14 per cent abv. Fortified wines (see Production below) range from 15 per cent abv to 22 per cent abv.

II

Wine's Complexities

Wine is, arguably, the most complex of agricultural products. No other is capable of expressing so many sensually palpable nuances. These are the consequence of many factors, chief among them soil type, climatic conditions, grape or vine variety, and winemaking practices.

III

Production

The principle of winemaking is simple. Freshly harvested grapes are crushed to release their juice (known as must), which is rich in fermentable sugars. Airborne wild yeasts, or the addition of cultured yeasts to the must, provoke fermentation. The main products of fermentation are ethyl alcohol and carbon dioxide, the latter being released from the fermenting must as a gas. Fermentation normally ceases when all the fermentable sugars have been converted to alcohol and carbon dioxide, or when the concentration of alcohol reaches a level too high for the yeasts to tolerate. The must is now wine.

There are, however, many variants of this process. The main variants come into play in order to produce white wine, red (and pink, or rosé) wine, sparkling wine, and fortified wine. Other variants are used to improve the quality of any of the above wine styles.

The juice of most grapes, including most red grapes, is colourless. White grapes are quickly pressed after being harvested and the juice separated from the grape skins before fermentation to produce white wine. (If most of the red grape varieties are treated in this way, the result will also be a white wine; this technique of producing white wine from red grapes is widely practised, for example, in the Champagne region of France. It is not, however, possible to make a red wine from white grapes.)

To make red wine, by contrast, red grapes are merely crushed before spending a part or the whole of their fermentation period, plus in many cases a period of pre- or post-fermentation maceration, or soaking, in contact with the grape skins. All of the colouring matter, plus many flavour compounds and tannins, are stored in grape skins, and fermentation and maceration release these. Their release is often intensified by techniques of mechanical rousing, or stirring, during this period.

Pink or rosé wine is generally made using red grapes which are left in contact with their skins for a short period only; it is less commonly made by blending red and white wine.

Sparkling wine (which contains dissolved carbon dioxide, released as bubbles after the bottle is opened) is made by a number of different methods. The cheapest and simplest is carbonation, a technique widely used in soft-drink manufacture: carbon dioxide is pumped into wine, which is then bottled under pressure. Most primitive is the bottling of wine before its fermentation has been completed (practised in some parts of France, where it is known as the méthode ancestrale or rurale), resulting in lightly sparkling, sometimes sweetish wine with a sediment.

All of the other methods of producing sparkling wine involve a secondary fermentation. Further yeast and sugar are added to a base wine to provoke refermentation in some sort of sealed container. This may take place in a tank (the tank or Charmat method), the wine subsequently being bottled under pressure; or in a series of tanks (the continuous method). It may take place in a bottle, the contents subsequently being transferred to a tank and filtered before being rebottled (the transfer method). Most expensive and laborious of all is the champagne method (also known as the traditional or classic method), whereby the second fermentation takes place in a bottle, usually under cool conditions and with a period of post-fermentation storage. The wine's sediment is then propelled into the bottle's neck, from where (after passing the inverted bottles through a freezing solution) it is ejected as a frozen pellet, and the wine topped up. The finest sparkling wines produced around the world, including all champagnes, are made by the champagne method.

Fortified wines are made by adding high-strength spirit (usually brandy) to must or to partially fermented wine. The spirit precludes or arrests fermentation, thereby stabilizing the wine. If unfermented must is fortified (as for the French Pineau des Charentes or Muscat Vins de Liqueur) the resulting wine is very sweet; fortifying partially fermented wine (as for port and for France's Vins Doux Naturels) also produces a sweet finished wine. Fortifying fully fermented wine (as for Spain's sherry) produces a dry wine, though one which may subsequently be sweetened by other methods. The main quality-enhancing variants on wine-production methods involve temperature, physical manipulation, additions, container type, and storage stratagems.

Temperature, particularly the fermentation temperature, is an important variable. Most white wines are now cool-fermented under some form of refrigeration, to preserve crispness and freshness. Red wines, by contrast, are warm-fermented, often at the ambient harvest temperature. Optimum fermentation temperatures are thought to lie between 9°C and 18°C (48.2°F and 64.4°F) for white wines, and between 20°C and 30°C (68°F and 86°F) for red wines. Refrigeration is also used to stabilize wines before bottling.

In general, the less a wine is physically moved, the better its quality will be. Among the quality-enhancing manipulations, however, must be included the various forms of maceration undergone by red wines in order to extract colour, flavour, and tannin (or sometimes its converse: light, fruity, red wines are often produced by whole-berry fermentation, also known as carbonic maceration, whereby red grapes are neither crushed nor macerated but fermented whole in an anaerobic environment). Wine lees, sediment deposit, can add desired flavours to wine, and these lees may be agitated after fermentation to increase the flavour uptake by the wine. Clarification of musts or wines may be achieved by physical intervention such as centrifugation, the application of centrifugal force, as well as by gravity. Filtration is an important means of clarifying and stabilizing wine, though heavy filtration can be harmful to wine quality.

The main additions used in winemaking are, in cooler wine-growing regions, sugar or rectified must has to be added to the must in order to increase final alcohol levels (this is known as chaptalization); and, in warmer wine-growing regions, acidity added to must in order to improve balance in the finished wine (acid adjustment). Other additions include tannin, finings (to clarify the wine), and oak chips (as a flavouring). All red wines and some white wines undergo, after primary fermentation, the bacteriological conversion known as malolactic fermentation, and this may be ensured by the addition of lactic bacteria to fermenting must or wine.

The type of container in which the wine is stored also affects wine flavour. Some containers, such as stainless-steel tanks, are neutral, and are used for wines in which the flavour of fermented grapes alone is sought; wooden containers, by contrast, and in particular small wooden containers of new wood, may be used to modify and improve wine flavours. In this way oaked wines are produced.

All wines alter in flavour with age. Most wines suffer a deterioration in flavour with age, and are best consumed as young as possible. More expensive wines, on the other hand, both white and (more commonly) red, improve with storage, generally in bottle (ideal storage conditions are described in Wine Drinking below). Optimum storage periods are highly variable, but only a tiny minority of wines will improve with storage of more than ten years.

IV

National and Regional Characteristics

The production of wine is possible throughout the world's temperate zones (25° to 50° north and south). Within these regions, and especially in Europe, geographical origin has been the traditional way of distinguishing between wine types. Designations of geographical origin (such as France's Appellation d'Origine Contrôlée, or AOC, or AC, system) are based on soil type, climate factors, grape varieties, and local winemaking traditions.

In recent years, however, the energetic development of non-European vineyards and vineyards in areas with no viticultural tradition has led to the grape variety becoming as important a way of distinguishing between wine types as is geographical origin (a wine made exclusively or preponderantly from a single grape variety is known as a varietal wine). The reasons for this are that grape varieties are a comparatively simple way for consumers to gauge wine style and flavour; and grape-variety characteristics tend to precede those based on geographical origin in wines produced in new or young vineyard areas.

At the beginning of the 21st century France was the world's largest wine producer (60,235 hl in 1999), followed by Italy (58,073 hl), and then Spain (32,679 hl). Wine is produced throughout Italy and in much of Spain, whereas its production in France is localized and specialized.

France's claim to be the world's greatest wine-producing nation is also based on the fact that its wine culture has, until recent years, been one of unrivalled sophistication; moreover its influence on other wine-producing nations—via the propagation of its grape varieties, the spread of its wine-making techniques, and the inspiration its greatest bottles have provided—has been and continues to be profound.

Bordeaux is the largest of France's major wine regions. Its red wines have, since the 18th century, provided a benchmark for all fine-wine production, and their quality, consistency, and longevity have made top Bordeaux châteaux (literally, “castles”, the name used to describe Bordeaux wine estates) wines the blue-chip holdings of the wine-auction stock market. Despite this, one strand of Bordeaux's wine-production influence is in temporary eclipse elsewhere at present: the principle that the best wines are made from a blend of grape varieties.

Merlot is Bordeaux's most widely planted variety, usually blended with Cabernet Sauvignon, Cabernet Franc, and small amounts of Petit Verdot and Malbec. Sub-regional styles are a consequence of the exact composition of blends, in conjunction with soil and climate influences (generally maritime here). In the gravelly soils of the Médoc and the Graves, for example, Cabernet Sauvignon dominates blends, giving lithe, sometimes austere wines of great longevity; whereas in the calcareous soils of Saint-Èmilion or on the gravel-over-clay subsoils of Pomerol, Merlot is preponderant, giving a softer, rounder, and more voluptuous style of red wine. White wines, too, are produced in Bordeaux. The most famous of these is the sweet wine of Sauternes and Barsac, made by allowing Sémillon and Sauvignon Blanc grapes to become infected by a mould called Botrytis cinerea. (The mould dehydrates the grapes, concentrating their sugars, as well as adding a distinctively tangy flavour note of its own.)

In contrast to Bordeaux, the wines of Burgundy, both red and white, are varietal: red Burgundy (the region is known as Bourgogne in French) is made from Pinot Noir, and white Burgundy from Chardonnay. Burgundy is a much smaller area than Bordeaux, and nowhere in the wine-producing world is land classified so minutely; Burgundy's appellation system recognizes four tiers of quality (Grand Cru, Premier Cru, “village” wines, and regional wines), with quality levels altering with extreme frequency among its highly parcellated, limestone vineyards. Burgundy's climate is broadly continental. In stylistic terms, red Burgundy is a light- to medium-bodied, highly perfumed wine whose physical slightness belies the power of flavour it can unleash; white Burgundy, by contrast, is among the weightiest, firmest, and fullest of all French white wines, though its northern variant, Chablis, is characterized by distinctively stony, tight-grained flavours.

Other major French vineyard areas include Champagne, a chalk-soiled area where Chardonnay, Pinot Noir, and Pinot Meunier are used to produce sparkling wines of great balance and finesse; Alsace, a region bordering Germany where fruity white varietal wines are produced; the Loire Valley, chiefly noted for mouthwateringly dry and finely balanced sweet white wines; the Rhône Valley, a region of richly flavoured red wines, those from its northern sector being based on the Syrah grape variety; and Languedoc-Roussillon in the south, traditionally an area producing high-volume, low-quality table wines, but which in recent times has adapted with considerable success to the production of inexpensive varietal wines (sold as Vins de Pays), as well as AOC wines based on blends of local grape varieties grown on hill-sited plots.

Italy has an enormously diverse wine culture of great antiquity but, until recent times, of little sophistication. Its legacy of grape varieties, thought to exceed 2,000, is unmatched by any other country. Historically, Italy has been overwhelmingly a red-wine-drinking country, and its two most celebrated wine-producing regions, Tuscany and Piedmont, both produce red wines to the virtual exclusion of whites. Tuscan reds (most typically Chianti), comparatively light-bodied but capable of great depth and expressivity, are based on the Sangiovese grape variety. The most celebrated of Piedmontese reds, Barolo and Barbaresco, are both made from Nebbiolo, a grape capable of giving deeply perfumed mid-weight wines whose high tannin and acidity levels mean that many require long ageing; other Piedmontese specialities include the incisive, vibrant Barbera and the softer, lusher Dolcetto.

Italy's best white wines are produced in Friuli-Venezia Giulia, bordering Austria and Slovenia, where a wide range of chiefly varietal wines of fresh and fruity style is made. Italy's biggest wine-producing region, by contrast, is the island of Sicily, whose overproduction of unsaleable wine is a large problem for the European Union as a whole.

Spain has the largest area of vineyards in the world (1.2 million hectares/2.9 million acres in 1999, compared to 914,000 hectares/2.3 million acres for France and 909,000 hectares/2.2 million acres for Italy), but many of these are of low productivity, hence its third position after France and Italy in the world wine-producing league table. Its finest wines are its sherries, produced by fortification, oxidative ageing, and fractional blending in the Jerez area; and the soft red wines of Rioja and Ribera del Duero.

Among other European wine-producing nations, Germany is distinguished by its extraordinarily fruity and delicate white wines (Germany is now the world's sixth-largest wine producer at 12,296 hl in 1999); and Portugal for its two fortified wine styles, luscious port and the highly oxidized, heat-aged Madeira, produced on the island of the same name (Portugal is now the world's ninth-largest wine producer at 7,806 hl in 1999).

The United States is the world's fourth-largest wine producer (20,212 hl in 1999), and production there is among the most streamlined and sophisticated in the world. Overwhelmingly concentrated in California, most inexpensive wines are produced from Central Valley fruit by a small number of large or very large companies. Higher-quality wines are produced by a large number of small-scale producers in cooler regions nearer to the Pacific coast, of which the most celebrated are the Napa and Sonoma valleys. As in most non-European wine-producing areas, wines tend to be varietal, with richly flavoured Cabernet Sauvignon and lush, silky Chardonnay being the most important red and white varieties respectively. Zinfandel, now known to be the same variety as Italy's Primitivo, was for long regarded as California's “native” grape variety, yielding boisterously flavoured red wines and often insipid sweet rosé, sold as “white Zinfandel”.

The two most important South American wine-producing nations are Argentina (the world's fifth-largest wine producer at 15,888 hl in 1999) and Chile (the world's twelfth-largest wine producer at 4,807 hl in 1999). Whereas the overwhelming majority of Argentina's wines are made for and consumed by the domestic market, Chile is a successful exporter of the fresh, fruity, richly flavoured yet comparatively inexpensive wines that during the 1990s enjoyed growing international success.

This demand, in part, reflected the international impact of Australia's wine industry, which during the 1980s was able to produce wines of this sort, previously uncommon in Europe, through a combination of technical expertise and innovation in the winery with limitless sunshine on irrigated vineyards sited around or relatively near to the country's southern coast. Australia is now the world's seventh-largest wine producer (8,511 hl in 1999). In addition to producing flavourful yet inexpensive wines from areas like Riverina and the Murray Valley, Australia has also built a high-quality fine-wine industry based on regional specialities, such as dark, lushly flavoured Shiraz (Syrah) from the Barossa Valley and tight-grained, peppery Cabernet Sauvignon from Coonawarra.

New Zealand started building its wine industry in earnest as recently as the 1980s, but it has already had great international success with white wines of intense fruit flavours, often accompanied by appealing vegetal or herbaceous aromas. New Zealand Sauvignon Blanc, especially that from the Marlborough region at the northern end of the South Island, is now a world style benchmark. New Zealand’s total wine production was 602 hl in 1999.

South Africa's wine industry, chiefly based in the regions around Cape Town, but with a bulk-production region along the banks of the Orange River, was until 1992 dominated by the KWV, a grape-growers' cooperative, and the majority of its annual harvest each year was destined for distillation or the production of non-alcoholic grape-derived products. Wine producers, however, have responded to the challenge of increased overseas interest following the abandonment of apartheid with a wide range of wines of which the most internationally competitive so far have been inexpensive whites, often based on the Chenin Blanc grape (called Steen locally). The Cape's winelands have great potential, for both red and white wines of every quality level, though how quickly this potential is realized depends on continuing social and economic stability in the new South Africa. The country is now the world's eighth-largest wine producer (7,968 hl in 1999).