German Riesling labels, decoded.

The most common mistake with German Riesling is to read Spätlese as a word for sweet. Riesling Kabinett, Spätlese and Auslese are rungs of the Prädikat ladder. A Prädikat records how ripe the grapes were at harvest. It does not tell you how much sugar is left in the finished wine.

Ripe grapes can be fermented until almost no sugar remains. The winemaker can also stop the fermentation early, leaving natural sweetness in the wine. So a Spätlese can be dry, off-dry or distinctly sweet. To know which, you need one more word on the label and sometimes the name of the association the estate belongs to.

Riesling Kabinett, Spätlese and Auslese: a ladder of ripeness

Prädikatswein, the category that carries these terms, is graded by the ripeness of the grapes when they are picked. Ripeness is measured as must weight, the density of the juice, which comes mostly from its sugar. It is expressed in degrees Oechsle and the minimum for each rung differs between Germany's thirteen wine regions and between grape varieties. No sugar may be added before fermentation at any Prädikat level: all the ripeness has to come from the vineyard.

From the lightest to the richest:

• Kabinett. Delicate wines from ripe grapes, usually modest in alcohol.
• Spätlese. The name means late harvest. Riper grapes, more intensity and concentration, but not necessarily sweet.
• Auslese. Selected harvest. Fully ripe bunches with the unripe berries sorted out. Intense, often but not always sweet.
• Beerenauslese. Individually selected, overripe berries, usually affected by noble rot. Rich and sweet.
• Eiswein. Grapes frozen on the vine, picked in a hard frost (by law, at minus 7°C or colder) and pressed while still frozen, so only concentrated juice runs out.
• Trockenbeerenauslese. Berries shrunken and shrivelled by noble rot. Rare, rich and honeyed. The trocken in its name refers to the dried berries, not to a dry wine.

The diagram shows the split that matters when you buy. Kabinett, Spätlese and Auslese can be dry, off-dry or sweet, depending on how the wine was made. From Beerenauslese upwards, Eiswein included, the wines are always sweet.

Finding the word that means dry

The Prädikat gives you the ripeness. The sweetness is in a second word, usually printed close to it:

• Trocken. Dry. By law, no more than 4 g/L of sugar, a limit that rises to 9 g/L when the acidity is no more than 2 g/L below the sugar.
• Halbtrocken. Off-dry. No more than 12 g/L, rising to 18 g/L when the sugar exceeds the acidity by no more than 10 g/L.
• Feinherb. Also off-dry, but not defined by law, so its sweetness varies from one producer to the next.

When none of these words appears on a Kabinett, Spätlese or Auslese, expect some sweetness. The alcohol figure is a useful clue. Sugar that stays in the wine never became alcohol, so a lower number usually means a sweeter wine.

Riesling's high acidity balances its sugar, so a wine with real sweetness can still taste fresh and taut rather than heavy.

Read the Prädikat for ripeness and the word beside it for sweetness: the two answer different questions.

Vineyard names, the VDP and GG

Vineyard names follow a pattern. A single vineyard is usually named together with its village or district, most often with the village turned into an adjective: Wehlener Sonnenuhr is the Sonnenuhr vineyard of Wehlen, on the Mosel. Be careful with older labels. A Grosslage, a large collective site covering many vineyards, could be named in the same way, which made a blend from a wide area look like a single site. Germany's revised wine law is ending that confusion: a Grosslage name is to carry the word Region in front of it.

The VDP, an association of leading German estates, runs its own classification alongside the law. Its members' bottles carry an eagle on the capsule. It sorts wines into four levels by origin: Gutswein (estate wine), Ortswein (village wine), Erste Lage (first-class site) and, at the top, Grosse Lage (great site).

In the VDP's system, a Grosses Gewächs, or GG, is a dry wine from a Grosse Lage vineyard, sold in a bottle embossed with the GG mark. This is where to look for the most serious dry Riesling in Germany. Do not confuse Grosse Lage with Grosslage: one is the top of the VDP's ladder, the other a collective name that can cover many vineyards.

The VDP also changes how the Prädikat reads. As a rule, its members reserve Kabinett, Spätlese, Auslese and the higher terms for wines with natural sweetness, so at a VDP estate a Spätlese is a sweet style. The dry wine from the same great vineyard is the GG.

Four regions in one line each

• Mosel. Steep slate slopes above the Mosel, Saar and Ruwer. Fine, fruity wines with relatively low alcohol. The classic source of sweet Kabinett and Spätlese.
• Rheingau. South-facing slopes along the stretch where the Rhine flows west. Riesling covers most of the vineyard and, by tradition, the first Spätlese was made here, at Schloss Johannisberg in 1775.
• Nahe. Very diverse soils, which make it a good place to taste how site changes Riesling.
• Pfalz. One of Germany's sunniest and driest regions and the largest Riesling-growing area in the world. Wines of substance, with softer acidity than the Mosel and aromas of peach and apricot.

Many sweet Mosel wines are strikingly low in alcohol, which makes a glass of Mosel Kabinett one of the lightest serious wines you can pour.

How German Riesling ages

High acidity preserves wine and Riesling has plenty of it. Good examples age for decades, the sweet ones longest of all. With time the colour deepens from lemon-green to gold and the fruit turns to honey and toast. Many Rieslings also develop a note usually described as petrol, which some drinkers prize and others avoid.

Germany's climate is cool and marginal, so the year matters more here than in warm, stable regions. Because the Prädikat depends on ripeness at harvest, a warm year lets more grapes reach the higher rungs and a cool one lets fewer do so. That dependence on the weather makes reading vintage reports worth the effort for German wine. Give a young GG a few years before you judge it. For the wider picture, see the white wines that age well.

At the table

Riesling is a gift with spicy and Asian food. Low alcohol and a touch of sweetness soften chilli heat, where a strong wine would amplify it. Acidity cuts through fat, salt and soy.

• Off-dry Kabinett. Char siu, dim sum and sweet-savoury sauces, the classic moves in pairing wine with Cantonese food.
• Dry Riesling. Steamed fish with ginger and spring onion. Also sushi and sashimi, where it earns a place among the best wines for Japanese food.
• Spätlese with some sweetness. Spiced dishes, miso and sweet glazes.
• Auslese and above. Blue cheese, fruit desserts or simply a small glass on its own.

How to buy the Riesling you want

Decide how sweet you want the wine before you look at anything else, then read the label in this order.

1. For a dry wine, look for trocken or a GG from a VDP estate.
2. For gentle sweetness, choose a Kabinett or Spätlese without trocken, ideally from the Mosel. A low alcohol figure confirms the style.
3. For a dessert wine, go to Beerenauslese, Eiswein or Trockenbeerenauslese. A small glass each is plenty, so share the bottle.
4. Check for the VDP eagle, then check the producer's reputation, which matters more than any single term.

Buy at least two bottles of a Riesling you like and keep one for five years or more. Few white wines reward patience so well, which is why Riesling deserves a place in any first cellar plan.