The subjective sweetness of a wine

Wine

Wine is an alcoholic beverage, made of fermented fruit juice, usually from grapes. The natural chemical balance of grapes lets them ferment without the addition of sugars, acids, enzymes, or other nutrients. Grape wine is produced by fermenting crushed grapes using various types of yeast. Yeast...

 is determined by the interaction of several factors, including the amount of sugar in the wine to be sure, but also the relative levels of alcohol, acids, and tannins. Briefly: sugars and alcohol enhance a wine's sweetness; acids (sourness) and bitter tannins counteract it. These principles are outlined in the classic work by Emile Peynaud, The Taste of Wine.

History

Vintage: the Story of Wine, by 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. This method was advocated by Virgil

Virgil

Publius Vergilius Maro, usually called Virgil or Vergil in English , was an ancient Roman poet of the Augustan period. He is known for three major works of Latin literature, the Eclogues , the Georgics, and the epic Aeneid...

 and Martial

Martial

Marcus Valerius Martialis , was a Latin poet from Hispania best known for his twelve books of Epigrams, published in Rome between AD 86 and 103, during the reigns of the emperors Domitian, Nerva and Trajan...

 in Roman

Roman Empire

The Roman Empire was the post-Republican period of the ancient Roman civilization, characterised by an autocratic form of government and large territorial holdings in Europe and around the Mediterranean....

 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

Crete

Crete is the largest and most populous of the Greek islands, the fifth largest island in the Mediterranean Sea, and one of the thirteen administrative regions of Greece. It forms a significant part of the economy and cultural heritage of Greece while retaining its own local cultural traits...

, 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

Passum

Passum was a raisin wine apparently developed in ancient Carthage and transmitted from there to Italy, where it was popular in the Roman Empire. The earliest surviving instruction constitutes the only known Carthaginian recipe...

 and the modern Italian equivalent, passito.

Stopping the fermentation also enhanced a wine's potential sweetness. In ancient times, this was achieved by submerging the amphoras in cold water till winter.

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

Mulsum

Mulsum is a small town in the district of Cuxhaven, in Lower Saxony, Germany. It is located on Wurster Landstraße, L129, between Dorum to the north-east, and Wremen to the south-west...

, wine freshly sweetened with honey and flavoured with spices, used as an apéritif, and also in the manufacture of conditum, which had similar ingredients but was matured and stored before drinking.

Residual sugar

Residual sugar is usually measured in grams of sugar per litre

Litre

pic|200px|right|thumb|One litre is equivalent to this cubeEach side is 10 cm1 litre water = 1 kilogram water The litre is a metric system unit of volume equal to 1 cubic decimetre , to 1,000 cubic centimetres , and to 1/1,000 cubic metre...

 of wine, often abbreviated to g/l or g/L. 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

Pentose

A pentose is a monosaccharide with five carbon atoms. Pentoses are organized into two groups. Aldopentoses have an aldehyde functional group at position 1...

. 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

Château d'Yquem

Château d'Yquem is a Premier Cru Supérieur wine from the Sauternes, Gironde region in the southern part of the Bordeaux vineyards known as Graves. In the Bordeaux Wine Official Classification of 1855, Château d'Yquem was the only Sauternes given this rating, indicating its perceived superiority...

 contain between 100 and 150 g/L of residual sugar. The sweetest form of the Tokaji

Tokaji

Tokaji is the name of the wines from the region of Tokaj-Hegyalja in Hungary and Slovakia. The name Tokaji is used for labeling wines from this wine district. This region is noted for its sweet wines made from grapes affected by noble rot, a style of wine which has a long history in this region...

, the Eszencia - contains over 450 g/L, with exceptional vintages registering 900 g/L. Such wines are balanced by carefully developed use of acidity

Acids in wine

The acids in wine are an important component in both winemaking and the finished product of wine. They are present in both grapes and wine, having direct influences on the color, balance and taste of the wine as well as the growth and vitality of yeasts during fermentation and protecting the wine...

. 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

Riesling

Riesling is a white grape variety which originated in the Rhine region of Germany. 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...

 and Chenin Blanc

Chenin Blanc

Chenin blanc , is a white wine grape variety from the Loire valley of France. Its high acidity means it can be used to make everything from sparkling wines to well-balanced dessert wines, although it can produce very bland, neutral wines if the vine's natural vigor is not controlled...

. Residual sugar typically refers to the sugar remaining after fermentation stops, or is stopping, but it can also result from the addition of unfermented must (a technique practiced in Germany and known as Süssreserve) or ordinary table sugar.

How sweet a wine will taste is also controlled by factors such as the acidity and alcohol

Alcohol

In chemistry, an alcohol is an organic compound in which the hydroxy functional group is bound to a carbon atom. In particular, this carbon center should be saturated, having single bonds to three other atoms....

 levels, the amount of tannin present, and whether the wine is sparkling or not. A sweet wine such as a Vouvray

Vouvray

Vouvray is a commune in the Indre-et-Loire department in central France.It is best known for its production of white wine, among some of the best rated in France.-References:*...

 can actually taste dry due to the high level of acidity. A dry wine can taste sweet if the alcohol level is elevated. 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

Sauternes (wine)

Sauternes is a French sweet wine from the Sauternais region of the Graves section in Bordeaux. Sauternes is made from Sémillon, Sauvignon Blanc, and Muscadelle grapes that have been affected by Botrytis cinerea, also known as noble rot. This causes the grapes to become partially raisined,...

 (including Barsac) or Tokaj

Tokaji

Tokaji is the name of the wines from the region of Tokaj-Hegyalja in Hungary and Slovakia. The name Tokaji is used for labeling wines from this wine district. This region is noted for its sweet wines made from grapes affected by noble rot, a style of wine which has a long history in this region...

, have a high level of residual sugar, which is carefully balanced with additional acidity to produce a harmonious result.

Süssreserve

Süssreserve is a wine

Wine

Wine is an alcoholic beverage, made of fermented fruit juice, usually from grapes. The natural chemical balance of grapes lets them ferment without the addition of sugars, acids, enzymes, or other nutrients. Grape wine is produced by fermenting crushed grapes using various types of yeast. Yeast...

 term referring to a portion of selected unfermented

Fermentation (wine)

The process of fermentation in wine turns grape juice into an alcoholic beverage. During fermentation, yeast interact with sugars in the juice to create ethanol, commonly known as ethyl alcohol, and carbon dioxide...

 grape must

Must

Must is freshly pressed fruit juice that contains the skins, seeds, and stems of the fruit. The solid portion of the must is called pomace; it typically makes up 7%–23% of the total weight of the must. Making must is the first step in winemaking...

, free of microorganisms, to be added to wine as a sweetening component. This technique was developed in Germany

Germany

Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...

 and is used with German-style wines such as semi-sweet Riesling

Riesling

Riesling is a white grape variety which originated in the Rhine region of Germany. 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...

 or Müller-Thurgau

Müller-Thurgau

Müller-Thurgau is a variety of white grape which was created by Hermann Müller from the Swiss Canton of Thurgau in 1882. It is a crossing of Riesling with Madeleine Royale. It is used to make white wine in Germany, Austria, Northern Italy, Hungary, England, in Australia, Czech Republic, Slovakia,...

. The technique not only raises the sugar level of the wine, but also lowers the amount of alcohol

Ethanol

Ethanol, also called ethyl alcohol, pure alcohol, grain alcohol, or drinking alcohol, is a volatile, flammable, colorless liquid. It is a psychoactive drug and one of the oldest recreational drugs. Best known as the type of alcohol found in alcoholic beverages, it is also used in thermometers, as a...

. Under German law, no more than fifteen percent of the final wine's volume may be the reserved juice. This practice is allowed also for Prädikatswein, the highest level in the German wine classification

German wine classification

German wine classification consists of several quality categories and is often the source of some confusion, especially among non-German speaking wine consumers. The official classification is set down in the wine law of 1971, although some changes and amendments have been made since then...

. It is often used for semi-sweet Kabinett

Kabinett

Kabinett , or sometimes Kabinettwein , is a German language wine term for a wine which is made from fully ripened grapes of the main harvest, typically picked in September, and are usually made in a light style...

 and Spätlese

Spätlese

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...

, but more rarely for Auslese

Auslese

Auslese is a German language wine term for a late harvest wine and is a riper category than Spätlese in the Prädikatswein category of the Austrian and German wine classification. The grapes are picked from selected very ripe bunches in the autumn , and have to be hand picked...

 and upward.

The use of Süssreserve gives a different composition of sugars in the wine in comparison to arrested fermentation. Grape must contains mainly the sugars glucose

Glucose

Glucose is a simple sugar and an important carbohydrate in biology. Cells use it as the primary source of energy and a metabolic intermediate...

 and fructose

Fructose

Fructose, or fruit sugar, is a simple monosaccharide found in many plants. It is one of the three dietary monosaccharides, along with glucose and galactose, that are absorbed directly into the bloodstream during digestion. Fructose was discovered by French chemist Augustin-Pierre Dubrunfaut in 1847...

. When wine ferments, glucose is fermented at a faster rate than fructose. Thus, arresting fermentation when a significant portions of the sugars have fermented gives a wine where the residual sugar consists mainly of fructose, while the use of Süssreserve will give a wine where the sweetness comes from a mixture of glucose and fructose.

Terms used to indicate sweetness of wine

According to EU regulation 753/2002, the following terms may be used on the labels of table wine

Table wine

Table wine is a wine term with two different meanings: a wine style; and a quality level within wine classification.In the United States, table wine primarily designates a wine style - ordinary wine which is neither fortified nor sparkling....

s and quality wines:

	Dry	Medium Dry	Medium	Sweet:
Sweetness	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	less than 10 g/l below sugar
Bosnian/Croatian	suho	polusuho	poluslatko	slatko
Bulgarian	сухо	полусухо	полусладко	сладко
Czech	suché	polosuché	polosladké	sladké
Chinese	干葡萄酒	半干葡萄酒	半甜葡萄酒	甜葡萄酒
Danish	tør	halvtør	halvsød	sød
Dutch	droog	halfdroog	halfzoet	zoet
English	dry	medium dry	medium, medium sweet	sweet
Estonian	kuiv	poolkuiv	poolmagus	magus
Farsi (Persian)	talkh (تلخ)	gass (گس)		shirin(شیرین)
Finnish	kuiva	puolikuiva	puolimakea	makea
French	sec	demisec	moelleux	doux
German	trocken	halbtrocken	lieblich	süss
Greek	ξηρός	ημίξηρος	ημίγλυκος	γλυκός
Hungarian	száraz	félszáraz	félédes	édes
Italian	secco, asciuttto	abboccato	amabile	dolce
Latvian	sausais	pussausais	pussaldais	saldais
Lithuanian	sausas	pusiau sausas	pusiau saldus	saldus
Polish	wytrawne	półwytrawne	półsłodkie	słodkie
Portuguese	seco	meio seco, adamado	meio doce	doce
Romanian	sec	demisec	demidulce	dulce
Russian	сухое	полусухое	полусладкое	сладкое
Serbian	suvo	polusuvo	poluslatko	slatko
Slovak	suché	polosuché	polosladké	sladké
Slovenian	suho	polsuho	polsladko	sladko
Spanish	seco	semiseco	semidulce	dulce
Swedish	torrt	halvtorrt	halvsött	sött
Turkish	sek	dömisek	yarıtatlı	tatlı
Ukrainian	сухе	напівсухе	напівсолодке	солодке

Terms used to indicate sweetness of sparkling wine

Sparkling wines have different ratings revised According to COMMISSION REGULATION (EC) No 607/2009 of 14 July 2009

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+

But note 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 considerable leeway.

EXAMPLE: A sparkling wine with 9 grams per litre of residual sugar may be labelled as either:

1. The drier, less sweet classification of Extra Brut (9 grams - 3 grams = 6 grams per litre); OR

2. The slightly sweeter classification of Brut or even Extra Dry/Extra Sec/Extra Seco (9 grams + 3 grams = 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+

Wine producing countries

In the United States, the wine industry measures the sweetness of must

Must

Must is freshly pressed fruit juice that contains the skins, seeds, and stems of the fruit. The solid portion of the must is called pomace; it typically makes up 7%–23% of the total weight of the must. Making must is the first step in winemaking...

 and wine in degrees Brix

Brix

Degrees Brix is the sugar content of an aqueous solution.One degree Brix is 1 gram of sucrose in 100 grams of solution and represents the strength of the solution as percentage by weight . If the solution contains dissolved solids other than pure sucrose, then the °Bx is only approximate the...

.

In France, the Baumé scale

Baumé scale

The Baumé scale is a pair of hydrometer scales developed by French pharmacist Antoine Baumé in 1768 to measure density of various liquids. The unit of the Baumé scale has been notated variously as degrees Baumé, B°, Bé° and simply Baumé . One scale measures the density of liquids heavier than water...

 is occasionally used. Sélection de Grains Nobles (SGN) is French

French language

French is a Romance language spoken as a first language in France, the Romandy region in Switzerland, Wallonia and Brussels in Belgium, Monaco, the regions of Quebec and Acadia in Canada, and by various communities elsewhere. Second-language speakers of French are distributed throughout many parts...

 for "selection of noble berries" and refers to wine

Wine

Wine is an alcoholic beverage, made of fermented fruit juice, usually from grapes. The natural chemical balance of grapes lets them ferment without the addition of sugars, acids, enzymes, or other nutrients. Grape wine is produced by fermenting crushed grapes using various types of yeast. Yeast...

s made from grape

Grape

A grape is a non-climacteric fruit, specifically a berry, that grows on the perennial and deciduous woody vines of the genus Vitis. Grapes can be eaten raw or they can be used for making jam, juice, jelly, vinegar, wine, grape seed extracts, raisins, molasses and grape seed oil. Grapes are also...

s affected by noble rot

Noble rot

Noble rot is the benevolent form of a grey fungus, Botrytis cinerea, affecting wine grapes. Infestation by Botrytis requires moist conditions, and if the weather stays wet, the malevolent form, "grey rot", can destroy crops of grapes...

. SGN wines are sweet dessert wines with rich, concentrated flavours. Alsace wine

Alsace wine

Alsace wine or Alsatian wine is produced in the Alsace region in France and is primarily white. These wines, which for historical reasons have a strong Germanic influence, are produced under three different Appellations d'Origine Contrôlées : Alsace AOC for white, rosé and red wines, Alsace Grand...

s were the first to be described as Sélection de Grains Nobles, with the legal definition introduced in 1984. 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, must/wine sweetness is measured with the Oechsle scale and below are ranges for Riesling

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 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 Hungary, the region of Tokaj-Hegyalja

Tokaj-Hegyalja

Tokaj-Hegyalja is a historical wine region located in southeastern Slovakia and northeastern Hungary. Hegyalja means "foothills" in Hungarian, and this was the original name of the region....

 has a more graduated terminology to describe Tokaji

Tokaji

Tokaji is the name of the wines from the region of Tokaj-Hegyalja in Hungary and Slovakia. The name Tokaji is used for labeling wines from this wine district. This region is noted for its sweet wines made from grapes affected by noble rot, a style of wine which has a long history in this region...

 Aszú dessert wines:

Minimum residual sugar	Description
60	3 puttonyos Puttonyos Puttonyos is the name given to denote the level of sugar and hence the sweetness of Hungarian dessert wine, called Tokaji . It is traditionally measured by the number of hods of sweet botrytised or nobly rotted grapes added to a barrel of wine, but is now measured in grams of residual sugar...
90	4 puttonyos
120	5 puttonyos
150	6 puttonyos
180	Aszú-Eszencia
450+	Eszencia

In Czech Republic and Slovakia, the Normalizovaný Muštomer

Normalizovaný muštomer

Normalizovaný moštoměr is a scale used in the Czech Republic and Slovakia for measuring the sweetness of wine must. 1 °NM indicates 1 kg of sugar in 100 litres of must....

(°NM) scale is used. The scale measures kg of sugar in 100 l of must. ČSN and STN 257621 - 1.3.1987