As you may know, Rioja is a wine that is dominated by Tempranillo grapes. Despite this, it remains a wine based on the art of blending. Besides the dominate Tempranillo, Rioja calls on the services of Grenache, Mazuelo (aka Carignan) and Graciano. There are even some exceptional examples of other grapes being allowed into individual bodegas’ productions, like Cabernet being allowed at the Marques de Riscal. This can occur because use of these so-called “foreign grapes” predates the creation of the current set of Rioja winemaking rules.
Blending grapes allows a wine maker to compensate for some of the vagaries of each growing season, though the fundamental nature of the wine produced may turn out to be stylistically different. In Rioja, vintage variation may end up being more about the style of a specific vintage vis-à-vis its peers, as opposed to the quality.
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