Late harvest wine in the sun to concentrate their sugar. Late harvest wine Late harvest wine is wine made from grapes left on the vine longer than usual. "Late harvest" is usually an indication of a sweet dessert wine, such as late harvest Riesling. Late harvest grapes are often more similar to raisins, but have been naturally dehydrated while on the vine. Botrytis cinerea, or "noble rot", is a mold that causes grapes to lose nearly all of their water content. Wines made from botrytis-affected grapes are generally very sweet. Botrytis cinerea is a fungus that affects many wine grapes and causes them
Phenolic content in wine into wine, most notably vanillin which adds vanilla aroma to wines. Most wine phenols are classified as secondary metabolites and were not thought to be active in the primary metabolism and function of the grapevine. However, there is evidence that in some plants flavonoids play a role as endogenous regulators of auxin transport. They are water-soluble and are usually secreted into the vacuole of the grapevine as glycosides. "Vitis vinifera" produces many phenolic compounds. There is a varietal effect on the relative composition. In red wine, up to 90% of the wine's phenolic content falls under the classification of flavonoids.