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Botrytis cinerea: what noble rot is, and how it makes great sweet wine
The fungus behind Sauternes, Tokaji and Trockenbeerenauslese: how it works, how to say it, where it happens, and the wines to try.
Updated October 2026
Rewritten by Alper Billik, Advanced Sommelier
4 min read
The short answer: Botrytis cinerea is a fungus. In damp weather it is a disease, grey rot, that ruins grapes. But when misty mornings are followed by dry, sunny afternoons, it turns into noble rot: it pierces the skins of ripe white grapes, water evaporates, and the berries shrivel. What is left is concentrated sugar, acidity and flavour: the raw material of Sauternes, Tokaji Aszú and Trockenbeerenauslese.
How to pronounce it
Botrytis cinerea: roughly “boh-TRY-tiss sin-EH-ree-uh”. Most sommeliers just say noble rot. The French call it pourriture noble, the Germans Edelfäule, and in Tokaj the shrivelled berries are called aszú.
How noble rot works
- Morning mist from a river or lake keeps the bunches damp, and the fungus takes hold on the skins.
- Warm, dry afternoons stop it spreading into destructive grey rot.
- The berries shrivel. Water evaporates through the damaged skins, so sugar and acidity concentrate. The fungus also changes the grape's chemistry and adds flavours of its own.
- It is uneven. Some berries are rotten, some are not, so the best estates pick by hand in several passes through the vineyard (tries in French), sometimes berry by berry.
- Yields are tiny and some years give nothing at all, which is why these wines are rare and never cheap.
Thin-skinned white grapes in tight bunches catch it best: Sémillon, Furmint, Riesling and Chenin Blanc above all. On red grapes botrytis is almost always unwelcome, because it damages colour and flavour.
What botrytised wine tastes like
Sweet, but never only sweet. Think honey, dried apricot, marmalade, candied citrus and quince, often with a note of saffron or ginger that tasters call simply “botrytis”. The texture is rich, almost oily. The good ones finish fresh, because the acidity is concentrated along with the sugar. The best keep for decades and turn deeper gold, then amber.
Where noble rot wines come from
| Region | Wine | Grapes | Why it works there |
|---|---|---|---|
| Bordeaux, France | Sauternes, Barsac; also Cadillac, Loupiac, Sainte-Croix-du-Mont, Cérons | Sémillon, Sauvignon Blanc, Muscadelle | The cool Ciron river meets the warmer Garonne and makes autumn mists |
| Tokaj, Hungary | Tokaji Aszú, Eszencia | Mainly Furmint and Hárslevelű | Two rivers, the Bodrog and the Tisza, and long autumns |
| Germany | Beerenauslese (BA), Trockenbeerenauslese (TBA) | Mainly Riesling | River valleys such as the Mosel and the Rheingau |
| Austria | Ausbruch, Beerenauslese, TBA | Welschriesling, Chardonnay and others | Lake Neusiedl in Burgenland; Ruster Ausbruch has its own DAC since 2020 |
| Loire, France | Coteaux du Layon, Quarts de Chaume, Bonnezeaux | Chenin Blanc | Morning mists from the Layon and the Loire |
| Alsace, France | Sélection de Grains Nobles (SGN) | Riesling, Gewurztraminer, Pinot Gris, Muscat | Dry, sunny autumns behind the Vosges |
- Bordeaux, France
- WineSauternes, Barsac; also Cadillac, Loupiac, Sainte-Croix-du-Mont, Cérons
- GrapesSémillon, Sauvignon Blanc, Muscadelle
- Why it works thereThe cool Ciron river meets the warmer Garonne and makes autumn mists
- Tokaj, Hungary
- WineTokaji Aszú, Eszencia
- GrapesMainly Furmint and Hárslevelű
- Why it works thereTwo rivers, the Bodrog and the Tisza, and long autumns
- Germany
- WineBeerenauslese (BA), Trockenbeerenauslese (TBA)
- GrapesMainly Riesling
- Why it works thereRiver valleys such as the Mosel and the Rheingau
- Austria
- WineAusbruch, Beerenauslese, TBA
- GrapesWelschriesling, Chardonnay and others
- Why it works thereLake Neusiedl in Burgenland; Ruster Ausbruch has its own DAC since 2020
- Loire, France
- WineCoteaux du Layon, Quarts de Chaume, Bonnezeaux
- GrapesChenin Blanc
- Why it works thereMorning mists from the Layon and the Loire
- Alsace, France
- WineSélection de Grains Nobles (SGN)
- GrapesRiesling, Gewurztraminer, Pinot Gris, Muscat
- Why it works thereDry, sunny autumns behind the Vosges
Two facts worth knowing. Since the 2013 vintage, every Tokaji Aszú must have at least 120 g/l of sugar; the old 3 and 4 puttonyos styles are gone, and the puttonyos number is now optional on the label. And Eiswein is a different thing: Wines of Germany notes that classic ice wine is made from frozen grapes that are not affected by noble rot.
Producers to look for
| Producer | Where | The wine |
|---|---|---|
| Château d'Yquem | Sauternes | The only Premier Cru Supérieur of the 1855 classification |
| Royal Tokaji | Mád, Tokaj | Tokaji Aszú, picked berry by berry |
| Dr. Loosen | Mosel | Riesling Beerenauslese and Trockenbeerenauslese |
| Domaine des Baumard | Rochefort-sur-Loire, Anjou | Quarts de Chaume from Chenin Blanc |
| Weingut Kracher | Illmitz, Burgenland | Trockenbeerenauslese by Lake Neusiedl |
- Château d'Yquem
- WhereSauternes
- The wineThe only Premier Cru Supérieur of the 1855 classification
- Royal Tokaji
- WhereMád, Tokaj
- The wineTokaji Aszú, picked berry by berry
- Dr. Loosen
- WhereMosel
- The wineRiesling Beerenauslese and Trockenbeerenauslese
- Domaine des Baumard
- WhereRochefort-sur-Loire, Anjou
- The wineQuarts de Chaume from Chenin Blanc
- Weingut Kracher
- WhereIllmitz, Burgenland
- The wineTrockenbeerenauslese by Lake Neusiedl
How to serve and pair it
- Cold, but not icy: take it from the fridge a few minutes before serving.
- Small pours. A bottle of sweet wine goes a long way; half bottles are common.
- Blue cheese is the classic: Sauternes with Roquefort.
- Foie gras, and fruit tarts that are less sweet than the wine.
- Savoury dishes too: Bordeaux's wine council's own site suggests lobster in butter.
For the glass, see the best glass for Sauternes. For Chenin Blanc's sweet side, read about Coteaux du Layon. Studying for an exam? Botrytis also appears in the vine diseases guide, and SOMM DIGI AI can quiz you on sweet wines in seconds.
Questions people ask
What is the difference between noble rot and grey rot?
Same fungus, different weather. With mist and then dry sun, it concentrates ripe grapes: noble rot. With damp all day, it destroys them: grey rot.
Are botrytised wines always sweet?
The famous ones are, and nearly all are. Noble rot is wanted almost only for sweet wine; in dry wines winemakers usually try to keep it out.
Why are noble rot wines expensive?
Tiny yields, picking by hand in several passes, long ageing and the risk of losing the whole crop in a wet autumn.
How long do botrytised wines last?
The best Sauternes, Tokaji Aszú, TBA and Quarts de Chaume can age for decades. Simpler ones are lovely within a few years.
Is ice wine made with noble rot?
No. Classic Eiswein comes from healthy grapes frozen on the vine.
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