What is Noble Rot?
Yes, rotting grapes can be a good thing! Noble rot is caused by the fungus called “botrytis”. Botrytis affects ripe grapes that are exposed to too much moisture. This is actually the same gray fungus that you often find on strawberries. (Maybe good for making strawberry wine, but don’t eat.) After fermenting the grapes into wine, the finished wine is clean and safe to drink.
Why Noble Rot wines are sweet.
Noble rot makes these grapes shrivel up like raisins, creating an intensely concentrated grape. This allows winemakers to create wines that still have high sugar levels after fermentation.
In fermentation, yeast turns sugars into alcohol and carbon dioxide. If there’s sugar left over after the yeast is done, the finished wine is sweet!
At the best vineyards, harvesters actually go through the vines several times, picking only the rotted grapes. This labor-intensive harvesting creates the most concentrated wines.
These wines have intense flavors and have a honey-like sweetness. They go great with desert–if you’d like to try one, look for a Sauternes from France or a Spätlese Riesling from Germany.