Some thoughts on terroir: different expressions of Touriga Nacional
Regular readers will know that I'm really interested by the way that different soils influence the flavour of wine. It's usually referred to as 'terroir', but there's more to terroir than just soils. Climate also plays a big role.
Portugal has a great demonstration of terroir in action. Consider the different expressions of Touriga Nacional in the Dao and the Douro regions. Yes, the climates are a little different (Douro is warmer and drier), but one of the chief differences is the soils.
Pictured above is a typical Dao soil type: sandy granite. Below we have the signature soil of the Douro: schist. Both are good vineyard soils in that they limit vigour and are free draining, but Touriga is quite different when grown on each.
This is perhaps a big generalization, but Dao Touriga is brighter, fresher and more aromatic, with distinctive floral/violet aromas, and red berry and black cherry fruits. Douro Touriga is typically richer and denser, with more palate weight and some meaty blackberry fruit. It can be floral, but it's usually richer and meatier.
Both are fantastic. I think Douro Touriga is usually best as part of a blend, though. Dao Touriga is also usually blended, but I think it can stand up on its own as a single variety. Still, generally speaking, Touriga is a fantastic blend component, and that's the way it is most effectively used.