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
White wine it flavours the wine giving it a scent of toast, butter, and vanilla but it also helps to mature it by providing a very small regular quantity of oxygen through the wooden walls. This oxygen helps to polymerize the components of the wine making it less aggressive and more balanced. The blending consists of mixing different wines in order to obtain the desired final blend. This assembly can be of varietals (in the case of Bordeaux wines or wines from the Languedoc-Roussillon), or blending of a vintage with varieties (in the case of champagne). This blending may be purely quantitative: