The greyer the berry the sweeter the juice?
Have you ever enjoyed an Auslese or Beerenauslese wine from Germany or even an Italian Amarone? If so, then you’ve probably consumed wines that are derived from grapes with a grey fungus called Botrytis cinerea. A botrytized wine comes from grapes covered in grey mold and is commonplace, especially in German wines. Boytris is caused by a continually humid environment that can lead to a destructive form of the fungus called gray rot that will destroy whole harvests of grapes. If wet weather conditions are followed by a drier condition it leads to noble rot (Pourriture Noble in French) which is a benevolent form of Botrytis cinerea.
When grapes are picked during certain beneficial stages of this process they yield sweet concentrated yet fine wines. Many times noble rot does not affect a ripened bunch of grapes simultaneously, so the grapes must harvested using a number of passes through a vineyard to select grapes at the right stage of infection. The grey fungus thrives off the water in the grapes, leaving behind a high concentration of fruity acids and sugars. This leads to a wine that has high concentrations of sugars and acidity.
