The subjective sweetness of a wine is determined by the interaction of several factors, including the amount of sugar in the wine, but also the relative levels of alcohol, acids, and tannins. Sugars and alcohol enhance a wine's sweetness, while acids cause sourness and bitter tannins cause bitterness. These principles are outlined in the 1987 work by Émile Peynaud, The Taste of Wine. [1]
Vintage: The Story of Wine, a book authored by British wine writer Hugh Johnson, presents several methods that have been used throughout history to sweeten wine. The most common way was to harvest the grapes as late as possible. [2] This method was advocated by Virgil and Martial in Roman times. In contrast, the ancient Greeks would harvest the grapes early, to preserve some of their acidity, and then leave them in the sun for a few days to allow them to shrivel and concentrate the sugar. In Crete, a similar effect was achieved by twisting the stalks of the grape to deprive them of sap and letting them dry on the vine—a method that produced passum and the modern Italian equivalent, passito. [2]
Stopping the fermentation also enhanced a wine's potential sweetness. In ancient times, this was achieved by submerging the amphorae in cold water till winter. [2]
Wine can also be sweetened by the addition of sugar in some form, after fermentation is completed – the German method like the Süssreserve . In Roman times, this was done in preparing mulsum, wine freshly sweetened with honey and flavored with spices, used as an apéritif, and also in the manufacture of conditum, which had similar ingredients but was matured and stored before drinking. It was also common from the Roman era until quite recently to sweeten wine with sugar of lead, a toxic substance that increases the apparent sweetness of wines and other beverages. The practice continued well into the 19th century, although the leading was mostly restricted to very cheap wines after the harmful nature of lead was demonstrated in the 17th century. [3]
Among the components influencing how sweet a wine will taste is residual sugar. It is usually measured in grams of sugar per litre of wine, often abbreviated to g/L or g/L. Residual sugar typically refers to the sugar remaining after fermentation stops, or is stopped, but it can also result from the addition of unfermented must (a technique practiced in Germany and known as Süssreserve) or ordinary table sugar.
Even among the driest wines, it is rare to find wines with a level of less than 1 g/L, due to the unfermentability of certain types of sugars, such as pentose. By contrast, any wine with over 45 g/L would be considered sweet, though many of the great sweet wines have levels much higher than this. For example, the great vintages of Château d'Yquem contain between 100 and 150 g/L of residual sugar. The sweetest form of the Tokaji, the Eszencia, contains over 450 g/L, with exceptional vintages registering 900 g/L. Such wines are balanced, keeping them from becoming cloyingly sweet, by carefully developed use of acidity. This means that the finest sweet wines are made with grape varieties that keep their acidity even at very high ripeness levels, such as Riesling and Chenin blanc.
How sweet a wine will taste is also controlled by factors such as the acidity and alcohol levels, the amount of tannin present, and whether the wine is sparkling or not. A sweet wine such as a Vouvray can actually taste dry due to the high level of acidity. A dry wine can taste sweet if the alcohol level is elevated. [1] : 198–199 Medium and sweet wines have a perception among many consumers of being of lower quality than dry wines. However, many of the world's great wines, such as those from Sauternes (including Barsac) or Tokaj, have a high level of residual sugar, which is carefully balanced with additional acidity to produce a harmonious result.
Süssreserve (German : Süßreserve; lit. 'sweet reserve ') is a wine term referring to a portion of selected unfermented grape must, free of microorganisms, to be added to wine as a sweetening component. This technique was developed in Germany and is used with German-style wines such as semi-sweet Riesling or Müller–Thurgau. [4] The technique not only raises the sugar level of the wine, but also lowers the amount of alcohol. Under German law, no more than fifteen percent of the final wine's volume may be the reserved juice. [5] This practice is allowed also for Prädikatswein, the highest level in the German wine classification. It is often used for semi-sweet Kabinett and Spätlese, but more rarely for Auslese and upward.
The use of Süssreserve results in a different composition of sugars in the wine in comparison to residual sugar from arrested fermentation. Grape must contains mainly the sugars glucose and fructose. When wine ferments, glucose is fermented at a faster rate than fructose. Thus, arresting fermentation after a significant portion of the sugars have fermented results in a wine where the residual sugar consists mainly of fructose, while the use of Süssreserve will result in a wine where the sweetness comes from a mixture of glucose and fructose.
According to EU regulation 753/2002, [6] [7] the following terms may be used on the labels of table wines and quality wines.
Dry | Medium dry | Medium | Sweet | |
---|---|---|---|---|
Sugar | up to 4 g/L | up to 12 g/L | up to 45 g/L | more than 45 g/L |
If balanced with suitable acidity | up to 9 g/L | up to 18 g/L | ||
suitable acidity as g/L tartaric | less than 2 g/L below sugar content | less than 10 g/L below sugar content |
[8] Sparkling wines have ratings according to Commission Regulation (EC) No 607/2009 of 14 July 2009. [9]
Rating | Sugar content (grams per litre) |
---|---|
Brut Nature (no added sugar) | 0–3 |
Extra Brut | 0–6 |
Brut | 0–12 |
Extra Dry, Extra Sec, Extra seco | 12–17 |
Dry, Sec, Seco | 17–32 |
Demi-sec, Semi-seco | 32–50 |
Doux, Sweet, Dulce | 50+ |
Article 58 points out "the sugar content may not differ by more than 3 grams per litre from what appears on the product label", so there is some leeway. For example, a sparkling wine with 9 grams per litre of residual sugar may be labelled as either the drier, less sweet, classification of Extra Brut (because 9 - 3 = 6 grams per litre), or the slightly sweeter classification of Brut or even Extra Dry/Extra Sec/Extra Seco (because 9 + 3 = 12 grams per litre).
The rules applicable to labellings before 14 July 2009 were:
Rating | Sugar content (grams per litre) |
---|---|
Brut Nature (no added sugar) | 0–3 |
Extra Brut | 0–6 |
Brut | 0–15 |
Extra Dry, Extra Sec, Extra seco | 12–20 |
Dry, Sec, Seco | 17–35 |
Demi-sec, Semi-seco | 33–50 |
Doux, Sweet, Dulce | 50+ |
In Austria, the Klosterneuburger Mostwaage (KMW) scale is used. The scale is divided into Klosterneuburger Zuckergrade (°KMW), and very similar to the Oechsle scale (1 °KMW =~ 5 °Oe). However, the KMW measures the exact sugar content of the must.
In Canada, the wine industry measures wine sweetness as grams of sucrose in 100 grams of grape juice or grape must at 20 °C in degrees Brix. [10]
In Czech Republic and Slovakia, the Normalizovaný Moštoměr (°NM) scale is used. The scale measures kg of sugar in 100 L of must.
In France, the Baumé scale is occasionally used. Sélection de Grains Nobles (SGN) is French for "selection of noble berries" and refers to wines made from grapes affected by noble rot. SGN wines are sweet dessert wines with rich, concentrated flavours. Alsace wines were the first to be described as Sélection de Grains Nobles, with the legal definition introduced in 1984. [11] The term is also used in some other wine regions of France, such as Loire.
Varieties | SGN since 2001 | SGN before 2001 |
---|---|---|
Gewürztraminer Pinot Gris | 279 grams per liter or 18.2% potential alcohol or 128 °Oe | 16.4% potential alcohol or 117 °Oe |
Riesling Muscat | 256 grams per liter or 16.4% potential alcohol or 117 °Oe | 15.1% potential alcohol or 108 °Oe |
In Germany, sweetness of must and wine is measured with the Oechsle scale, and below are ranges of minimum must weights for Riesling, depending on the region.
Kabinett – 67–82 °Oe
Spätlese – 76–90 °Oe
Auslese – 83–100 °Oe
Beerenauslese and Eiswein – 110–128 °Oe (Eiswein is made by late harvesting grapes after they have frozen on the vine and not necessarily affected by noble rot, botrytis, which is the case with Beerenauslese)
Trockenbeerenauslese – 150–154 °Oe (affected by botrytis)
In Hungary, Tokaj wine region (also Tokaj-Hegyalja wine region or Tokaj–Hegyalja) has a more graduated terminology to describe Tokaji Aszú dessert wines:[ citation needed ]
Minimum residual sugar | Description |
---|---|
60 | 3 puttonyos |
90 | 4 puttonyos |
120 | 5 puttonyos |
150 | 6 puttonyos |
180 | Aszú-Eszencia |
450+ | Eszencia |
In Spain, the rules applicable to the sweet and fortified Denominations of Origen Montilla-Moriles and Jerez-Xérès-Sherry [12] [13] are:
Fortified Wine Type | Alcohol % ABV | Sugar content (grams per litre) |
---|---|---|
Fino | 15-17 | 0–5 |
Manzanilla | 15-17 | 0–5 |
Amontillado | 16-17 | 0–5 |
Palo Cortado | 17-22 | 0–5 |
Oloroso | 17-22 | 0–5 |
Dry | 15-22 | 5–45 |
Pale Cream | 15.5-22 | 45–115 |
Medium | 15-22 | 5–115 |
Cream | 15.5-22 | 115-140 |
Pedro Ximénez | 15-22 | 212+ |
Moscatel | 15-22 | 160+ |
Dulce / Sweet | 15-22 | 160+ |
In the United States, the wine industry measures the sweetness of must and wine in degrees Brix.
Dessert wines, sometimes called pudding wines in the United Kingdom, are sweet wines typically served with dessert.
Riesling is a white grape variety that originated in the Rhine region. Riesling is an aromatic grape variety displaying flowery, almost perfumed, aromas as well as high acidity. It is used to make dry, semi-sweet, sweet, and sparkling white wines. Riesling wines are usually varietally pure and are seldom oaked. As of 2004, Riesling was estimated to be the world's 20th most grown variety at 48,700 hectares, but in terms of importance for quality wines, it is usually included in the "top three" white wine varieties together with Chardonnay and Sauvignon blanc. Riesling is a variety that is highly "terroir-expressive", meaning that the character of Riesling wines is greatly influenced by the wine's place of origin.
Winemaking, wine-making, or vinification is the production of wine, starting with the selection of the fruit, its fermentation into alcohol, and the bottling of the finished liquid. The history of wine-making stretches over millennia. There is evidence that suggests that the earliest wine production took place in Georgia and Iran around 6000 to 5000 B.C. The science of wine and winemaking is known as oenology. A winemaker may also be called a vintner. The growing of grapes is viticulture and there are many varieties of grapes.
Late harvest wine is wine made from grapes left on the vine longer than usual. Late harvest is usually an indication of a sweet dessert wine, such as late harvest Riesling. Late harvest grapes are often more similar to raisins, but have been naturally dehydrated while on the vine.
White wine is a wine that is fermented without skin contact. The colour can be straw-yellow, yellow-green, or yellow-gold. It is produced by the alcoholic fermentation of the non-coloured pulp of grapes, which may have a skin of any colour. White wine has existed for at least 4,000 years.
German wine is primarily produced in the west of Germany, along the river Rhine and its tributaries, with the oldest plantations going back to the Roman era. Approximately 60 percent of German wine is produced in the state of Rhineland-Palatinate, where 6 of the 13 regions (Anbaugebiete) for quality wine are situated. Germany has about 103,000 hectares of vineyard, which is around one tenth of the vineyard surface in Spain, France or Italy. The total wine production is usually around 10 million hectoliters annually, corresponding to 1.3 billion bottles, which places Germany as the eighth-largest wine-producing country in the world. White wine accounts for almost two thirds of the total production.
Must weight is a measure of the amount of sugar in grape juice (must) and, hence, indicates the amount of alcohol that could be produced if it is all fermented to alcohol, rather than left as residual sugar.
The German wine classification system puts a strong emphasis on standardization and factual completeness, and was first implemented by the German Wine Law of 1971. Nearly all of Germany's vineyards are delineated and registered as one of approximately 2,600 Einzellagen, and the produce from any vineyard can be used to make German wine at any quality level, as long as the must weight of the grapes reaches the designated minimum level. As the current German system does not classify vineyards by quality, the measure of wine ’quality’ is the ripeness of the grapes alone.
Spätlese is a German wine term for a wine from fully ripe grapes, the lightest of the late harvest wines. Spätlese is a riper category than Kabinett in the Prädikatswein category of the German wine classification and is the lowest level of Prädikatswein in Austria, where Kabinett is classified in another way. In both cases, Spätlese is below Auslese in terms of ripeness. The grapes are picked at least seven days after normal harvest, so they are riper and have a higher sugar content. Because of the weather, waiting to pick the grapes later carries a risk of the crop being ruined by rain. However, in warm years and from good sites much of the harvest will reach Spätlese level.
Malolactic conversion is a process in winemaking in which tart-tasting malic acid, naturally present in grape must, is converted to softer-tasting lactic acid. Malolactic fermentation is most often performed as a secondary fermentation shortly after the end of the primary fermentation, but can sometimes run concurrently with it. The process is standard for most red wine production and common for some white grape varieties such as Chardonnay, where it can impart a "buttery" flavor from diacetyl, a byproduct of the reaction.
Alsace wine or Alsatian wine is produced in the Alsace region in France and is primarily white wine. Because of its Germanic influence, it is the only Appellation d'Origine Contrôlée region in France to produce mostly varietal wines, typically from similar grape varieties to those used in German wine. Along with Austria and Germany, it produces some of the most noted dry Rieslings in the world as well as highly aromatic Gewürztraminer wines. Wines are produced under three different AOCs: Alsace AOC for white, rosé and red wines, Alsace Grand Cru AOC for white wines from certain classified vineyards and Crémant d'Alsace AOC for sparkling wines. Both dry and sweet white wines are produced.
Vendange tardive ("VT") means "late harvest" in French. The phrase refers to a style of dessert wine where the grapes are allowed to hang on the vine until they start to dehydrate. This process, called passerillage, concentrates the sugars in the juice and changes the flavours within it. The name is sometimes written as the plural form, vendanges tardives, referring to the fact that several runs through the vineyard are often necessary to produce such wines. In other countries such as Germany or Austria the term Spätlese is used to describe wine using the same making process.
The Oechsle scale is a hydrometer scale measuring the density of grape must, which is an indication of grape ripeness and sugar content used in wine-making. It is named for Ferdinand Oechsle (1774–1852) and it is widely used in the German, Swiss and Luxembourgish wine-making industries. On the Oechsle scale, one degree Oechsle (°Oe) corresponds to one gram of the difference between the mass of one litre of must at 20 °C and 1 kg. For example, must with a specific mass of 1084 grams per litre has 84 °Oe.
The glossary of wine terms lists the definitions of many general terms used within the wine industry. For terms specific to viticulture, winemaking, grape varieties, and wine tasting, see the topic specific list in the "See also" section below.
Sélection de Grains Nobles (SGN) is French for "selection of noble berries" and refers to wines made from grapes affected by noble rot. SGN wines are sweet dessert wines with rich, concentrated flavours. Alsace wines were the first to be described as Sélection de Grains Nobles, with the legal definition introduced in 1984, but the term is also seen in some other wine regions France, such as Loire.
Sugars in wine are at the heart of what makes winemaking possible. During the process of fermentation, sugars from wine grapes are broken down and converted by yeast into alcohol (ethanol) and carbon dioxide. Grapes accumulate sugars as they grow on the grapevine through the translocation of sucrose molecules that are produced by photosynthesis from the leaves. During ripening the sucrose molecules are hydrolyzed (separated) by the enzyme invertase into glucose and fructose. By the time of harvest, between 15 and 25% of the grape will be composed of simple sugars. Both glucose and fructose are six-carbon sugars but three-, four-, five- and seven-carbon sugars are also present in the grape. Not all sugars are fermentable, with sugars like the five-carbon arabinose, rhamnose and xylose still being present in the wine after fermentation. Very high sugar content will effectively kill the yeast once a certain (high) alcohol content is reached. For these reasons, no wine is ever fermented completely "dry". Sugar's role in dictating the final alcohol content of the wine sometimes encourages winemakers to add sugar during winemaking in a process known as chaptalization solely in order to boost the alcohol content – chaptalization does not increase the sweetness of a wine.
This glossary of winemaking terms lists some of terms and definitions involved in making wine, fruit wine, and mead.
In viticulture, ripeness is the completion of the ripening process of wine grapes on the vine which signals the beginning of harvest. What exactly constitutes ripeness will vary depending on what style of wine is being produced and what the winemaker and viticulturist personally believe constitutes ripeness. Once the grapes are harvested, the physical and chemical components of the grape which will influence a wine's quality are essentially set so determining the optimal moment of ripeness for harvest may be considered the most crucial decision in winemaking.
Slovak wine is produced in the southern part of Slovakia, which is divided into 6 wine-producing areas. Although Slovak wines except Tokaj are not well-known internationally, they are popular domestically and in neighbouring countries. The best wines are produced by medium-sized wineries with their own vineyards, with white wine production being most dominant, including the full range of historic sweet wines – ice wine, straw wine, and botrytized wine.
Wachau is one of Austria's most established and notable wine regions, specializing in dry wines made from Riesling and Grüner Veltliner. Located in Lower Austria along the Danube, west of Vienna and Krems an der Donau, it is one of the westernmost wine producing regions in Austria with only a few scattered plantings in Tyrol being further west. While most of Austria follows a wine classification systems based on ripeness and harvest must weight that parallels the German wine classification system, Wachau wines have a unique classification system. The three classification levels for Wachau wine include Steinfeder for wines up to 11.5% alcohol level, Federspiel for wines between 11.5–12.5% and Smaragd that must have a minimum of 12.5% alcohol level. Despite its renown, the Wachau is a small wine region that usually accounts for only around 3% of Austria's wine production.