Which grape is primarily used in the production of Port wine?

The primary grape used in the production of Port wine is indeed the Douro grape, which often includes Touriga Nacional among other varietals. The Douro Valley in Portugal is known for its unique terroir, which plays a significant role in the complexity and richness of Port.

Touriga Nacional is particularly valued for its high-quality fruit, contributing intense color, aroma, and tannin structure to the wine, making it ideal for the fortified style of Port. The combination of these grapes, along with the traditional winemaking techniques that include fortification during fermentation, leads to the characteristic sweetness and depth that Port wines are known for.

Other grape varieties like Tinta Roriz and Tinta Barroca are also commonly blended into Port, but Touriga Nacional is often the star of these blends, enhancing the wine's profile and aging potential. The choice of the specific varieties and the blending process are crucial in creating the different styles of Port, from Ruby to Tawny and Vintage.