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
Wine fraud of the wine. Today the practice of blending grape varieties together is commonly accepted (such as blending Cabernet Sauvignon and Merlot), except where such blending is against the regulation of a particular appellation (such as the controversy over the "Brunellopoli" scandal in Brunello di Montalcino). The gray area comes when inferior wine is being blended in with more expensive, higher quality wine in order to increase the total quantity of wine available to be sold at higher prices. This is a process known as "stretching" or "cutting in" the wine. During the 18th century, Bordeaux wine producers would often import