Trocken is German

German language

German is a West Germanic language, related to and classified alongside English and Dutch. With an estimated 90 – 98 million native speakers, German is one of the world's major languages and is the most widely-spoken first language in the European Union....

 for dry, and is used in the classification of German wine. On a wine label, it indicates a wine that is dry rather than off-dry (halbtrocken), sweeter (lieblich) or sweet (süß). Technically, trocken wines are not devoid of residual sugar, but have, at most, a few grams per liter, which can be perceptible but is not overtly sweet. Trocken is also used as a designation for Austrian wine

Austrian wine

Austrian wines are mostly dry white wines with some luscious dessert wines made around the Neusiedler See. About 30% of the wines are red, made from Blaufränkisch , Pinot Noir and locally bred varieties such as Zweigelt...

, but more rarely than in Germany, since many quality categories of Austrian wines are dry by default.

Somewhat confusingly, for Sekt and other sparkling wine

Sparkling wine

Sparkling wine is a wine with significant levels of carbon dioxide in it making it fizzy. The carbon dioxide may result from natural fermentation, either in a bottle, as with the méthode champenoise, in a large tank designed to withstand the pressures involved , or as a result of carbon dioxide...

s, trocken indicates a higher level of sugar than it does for non-sparkling wines. A Sekt trocken is best described as off-dry or semi-sweet, while a Sekt brut is completely dry.

Requirements

The maximum amount of sugar

Sugars in wine

The sugars in wine grapes are what make winemaking possible. During the process of fermentation, sugars are broken down and converted by yeasts into alcohol and carbon dioxide. Grapes accumulate sugars as they grow on the grapevine through the translocation of sucrose molecules that are produced...

 allowed for a trocken designation depends on the level of acid

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...

 in the wine. For wine low in acid, a maxium of 4 grams per liter sugar is allowed. If the acid level exceeds 2 grams per liter, the sugar may exceed the acid level by 2 grams per liter, up to a maximum of 9 grams of sugar per liter. Most high-quality German white wines have a high enough acidity to be allowed up to 9 grams per liter of sugar under the trocken level. When used, the requirements in Austria are exactly the same.

Sparkling wines

When used for sparkling wine, the term trocken actually means 17 to 35 grams per liter of sugar. This parallels the term sec ("dry") in French, which indicates a sparkling wine of the same sugar level as trocken. Drier wines are designated extra trocken at 12 to 20 grams of sugar per liter, while completely dry sparkling wines are given the designation brut (0–15 grams per liter) or extra brut (0–6 grams per liter).

Background

Until the invention of sterile filtration, most German wines were dry. Fermentation continued until all the sugar was consumed, leaving only miscellaneous unfermentable sugars. Only the occasional sweet rarity, made from extremely ripe grapes, kept any residual sugar. For most of the twentieth century, the style was typically sweeter low alcohol wines. Only since about 1990 has dry, trocken wine become popular, partly because many prefer it with food. Most exported German wine is still of the sweeter styles. While it appears in the term trockenbeerenauslese

Trockenbeerenauslese

Trockenbeerenauslese is a German language wine term for an intensely sweet dessert wine-style wine....

, trocken in that case refers to the dried grapes, not the dryness of the resulting wine.