What are the main white grape varieties found in Rioja DOCa?

The primary white grape varieties found in Rioja DOCa are indeed Viura, Garnacha Blanca, and Malvasia. Viura, also known as Macabeo in other regions of Spain, is the most widely planted white grape in the region and is essential for producing both youthful and age-worthy white wines. Garnacha Blanca contributes to the complexity and can add richness and body to blends. Malvasia is also used, typically in smaller quantities, to add aromatic qualities and freshness.

Other options listed include grape varieties that are not typically associated with the Rioja region. For instance, Albariño is primarily grown in the Rías Baixas region of Spain, known for its aromatic white wines. Chardonnay and Macabeo, while present in other Spanish wine regions, do not represent the core white varieties of Rioja DOCa. Lastly, Furmint is predominantly found in Hungary, and Verdejo is largely associated with Rueda, making them irrelevant for this particular question focused on Rioja white varietals.