Botrytis Cinerea - The Noble Rot!

Botrytis Cinerea is a naturally occurring unique phenomenon which if graces the vineyards (in favourable quantities) is loved by any dessert winemaker. Botrytis is a fungal rot and for this variety of rot to grow it needs to have early morning mists which will, in turn, create humidity and sunshine during the day is much needed. This rot appears in a lot of different countries and is known by various names like 'Pouriture Noble' in France, 'Edelfaule' in Germany and 'Noble Rot' in England.

@Morning Fog in Vineyards.

If we talk about sweet wine-producing regions, many of them are generally situated near a water body like a river or even a lake for that matter. Waterbodies help in creating an early morning mist which is very important for Botrytis to develop. You need to have sufficient sunshine which in turn will help the mist to disappear which will also help to limit the growth of the fungus and the warmth will ripen the grapes evenly. In some cases, even rain can trigger the fungus growth if after the rains the following weather is dry.

Certain grape varieties are usually more susceptible to this rot, because of their soft skin and close bunches which will not allow the airflow around the berries and the berries are closely stuck to each other so the fungus will spread easily. Some of the rot susceptible grapes are Semillon, Sauvignon Blanc, Chenin Blanc, Riesling, Gruner Veltliner and Furmint. It is not that every year the vineyard might get the infection as for the infection to occur it totally depends on the weather condition and atmosphere in the region.

It takes a lot of effort to make botrytis affected wines as the work is very labour intensive. Some of the botrytis wine prices can go very high due to that. The yields are heavily reduced and the risk of leaving the fruit on the vines for a longer time also adds to the cost. Birds love sweet berries and if they eating any berries or somehow splitting berries while eating will promote the grey rot to occur which can be very dangerous for a vineyard. The fungus doesn’t occur to all the berries in the vineyard together for that the harvesting happens in 2 or 3 tries. This is because the fungus takes time to reach all the berries.

The wines related to botrytis have been made for centuries where the conditions have been favourable. It is said that Hungarian Tokaj was the first botrytized wine to be made, according to the historical documents. Laczkó Máté Szepsi from Hungary who is the ancestor of Istevan Szepsi, first documented the Aszu process in the year 1630. Even there are few documents which were found listing the Aszu wine which is dated back to 1571. 

@Botrytis Developing on a bunch of grapes.

So how did the process reach France?

It is said that Tokaj wine was first sent by the Prince of Transylvania to Louis XIV of France in 1703, which was later referred as Vinum Regum or Rex Vinorum the meaning for those word being "King of wines and wine of Kings". This geared the production of botrytized dessert wines in Sauternes, France which was perfected in the mid-19th century.

The wines made from botrytis are loved all over the world and now even these wines are being produced all over the world. In Australia, it is produced in a way closer to Tokaj, but they cannot sell by the name of Tokay so it is sold as 'Topaque'. 

Chateau d'Yquem is one of the most renowned botrytis wines which one can ever have. It is one of the most expensive dessert wines on the planet today. The reason for it being so expensive is due to the popular 1855 Classification of Bordeaux carried out by Emperor Napoleon III for the 1855 Exposition Universelle de Paris, in which it was categorized under a Superior First Growth (Premier Cru Supérieur) and is the only one in its category.

@Chateau d'Yquem, Premier Cru Supérieur.

Botrytis shrivels and decays wine grapes thus intensifying its flavours and aromas and turns them into more viscous and sweeter wines.The descriptors of the botrytis are honey, ripe apricots, saffron, beeswax, ginger, dried fruit and orange marmalade. Botrytis is not only used to make dessert wines but is also used to make some really complex dry white wines in Alsace & Austria.

Some popular botrytis affected wines are:

• Sauternes, Bordeaux, France
• Ruster Ausbruch, Rust, Austria
• Tokaji Aszu, Hungary 
• Botrytis Semillon, Riverina, Australia
• Spätlese and above Riesling, Alsace, Germany

Article by - Nikhil Surve, Certified Sommelier.