Tasting fortified wines on Saturday, the point that wine structure really is key for recognition in a blind situation was once again reinforced in a major way. I

f you put side by side, and Amontillado, an Oloroso, a Sercial, and even a Verdelho, you will see that the colour is pretty much the same.  All are clearly "rancio" on the 1st sniff. And, with alcohol ranging from 18.5 to 19. to 20%, it is evident that you are in the presence of a fortified wine. And so, what sets them apart.  

Structure is the key.  The Amontillado and the Oloroso both have a much lower level of acidity compared to the Sercial and Verdelho.  In fact, acidity is what clearly sets the Madeiras from the Sherries... Let's see now, with a flight of each type, how the different wines compare and contrast each other...