Phenolic content in wine - quercetin. Like other flavonoids, the concentration of flavonols in the grape berries increases as they are exposed to sunlight. Some viticulturalists will use measurement of flavonols such as quercetin as an indication of a vineyard's sun exposure and the effectiveness of canopy management techniques. Anthocyanins are phenolic compounds found throughout the plant kingdom, being frequently responsible for the blue to red colors found in flowers, fruits and leaves. In wine grapes, they develop during the stage of "veraison" when the skin of red wine grapes changes color from green to red to black. As the sugars in the grape
The Fox and the Grapes while the mother contemplates them with her paws clasped behind her. There have also been the following musical settings: The Fox and the Grapes The Fox and the Grapes is one of the Aesop's fables, numbered 15 in the Perry Index. The narration is concise and subsequent retellings have often been equally so. The story concerns a fox that tries to eat grapes from a vine but cannot reach them. Rather than admit defeat, he states they are undesirable. The expression "sour grapes" originated from this fable. The fable of The Fox and the Grapes is one of the few