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 Grapes of Wrath sums up the book's influence: ""The Grapes of Wrath" may well be the most thoroughly discussed novel – in criticism, reviews, and college classrooms – of 20th century American literature." "The Grapes of Wrath" is referred to as a Great American Novel. At the time of publication, Steinbeck's novel "was a phenomenon on the scale of a national event. It was publicly banned and burned by citizens, it was debated on national radio; but above all, it was read." According to "The New York Times," it was the best-selling book of 1939 and 430,000 copies had been printed by February