Wine color practice of saignée (exposing wine to red grape skins for only a short period of time in order to give it a lighter feel closer to that of white wine) or by blending a white wine with a red wine. The presence of a complex mixture of anthocyanins and procyanidins can increase the stability of color in wine. As it ages, the wine undergoes chemical autoxidation reactions involving acetaldehyde of its pigments molecules. The newly formed molecules are more stable to the effect of pH or sulfite bleaching. The new compounds include pyranoanthocyanins like vitisins (A and B), pinotins and
American wine of the Eighteenth Amendment to the United States Constitution in 1920, which forbade the manufacturing, sale and transport of alcohol. Exceptions were made for sacramental wine used for religious purposes, and some wineries were able to maintain minimal production under those auspices, but most vineyards ceased operations. Others resorted to bootlegging. Home wine-making also became common, allowed through exemptions for sacramental wines and production for home use. Following the repeal of Prohibition in 1933, operators tried to revive the American wine-making industry, which was nearly ended. Many talented wine-makers had died, vineyards had been neglected or replanted with table grapes,