"Noble rot" is the term used – in certain circumstances – for the fungus Botrytis cinerea. The name derives from “grapes like ashes”. It’s a mould which attacks a variety of plants and most of the time it is a pest destroying the beauty and health of flowers and fruit. In the case of grapes, persistent damp conditions may cause the spread of the infection, and the fungus attacks and rots the grapes producing a condition called “grey rot” which is exactly as bad as it sounds. No beauty here. Just the opposite. But if the conditions are right, something else happens. If the fungus attacks the grapes but then dries out during the day, the fungus sucks the moisture from the berries and shrinks and shrivels them, concentrating acids, sugars and other solids. Such grapes carefully picked – in some cases one by one rather than bunch by bunch – produce an intense sweet but acid-rich wine with wonderful flavours of marmalade, peaches, apricots and an intense nose hinting of the botrytis itself. Gorgeous. Surprising. Beautiful.
Grapes heavily infested with Botrytis cinerea
Ideally the vineyards should grow in areas where mist comes from a lake or river allowing the infection to develop, but where the sun lifts the damp and the grapes dry. The great botrytis wine growing regions are Sauternes in France, Tokaji in Hungary and the Rheingau in Germany. But other areas produce wonderful examples, particularly Alsace and – yes, you guessed – South Africa.
Given the look of the infected grapes, one has to wonder who could have thought of making wine from them rather than discarding them along with their "grey rot" cousins.
In South Africa we can be more certain of the backstory. It was a German who introduced botrytis wines. Günter Brözel – first winemaker at modern Nederburg - used chenin blanc grapes affected with the mould to make a wine he called Nederburg Edelkeur. It remains South Africa’s premier example of the art. Stanley and I had the pleasure of sharing a bottle with friends from Eichborn publishers in Frankfurt at a delightful dinner there last Thursday. Although being on the doorstep of the Rheingau, they found it quite acceptable.
Nederburg Winemakers - Razvan Macici and Günter Brözel
Michael – Thursday