The olfactory receptors in the backs of our noses are directly connected to a whole archive of images in our brains. This library is more or less rich depending on our experiences from birth onward. It allows us to describe wine’s volatile compounds as they reach our retro-nasal receptors. For example, the furaneol found in Merlot is reminiscent of strawberries or caramel, two similar olfactory sensations. Amazingly, our brains can distinguish between 400,000 different odors.

Building a sophisticated sense of smell is a learning process, and your adeptness will increase with practice, just like learning a language. As with a language there are oral and written components, so with the sense of smell there are the nasal component (smelling the wine in the glass) and the retro-nasal component (rolling the wine around in your mouth). For the latter type, the volatile aromas reach the mucous membranes of the nose via the back of your palate. The two components of smell merge together to form one overall sensation.

Smelling a wine that has not been swirled will identify the wine’s most volatile components that are released automatically.

After swirling, these will be amplified and new aromas will emerge. This is the difference between the “first nose” and the “second nose” of a wine.

You will quickly be able to identify groups of aromas for the wine you are tasting, such as white and yellow flowers or fruit. The next step is, what type of fruit? Red fruit, such as gooseberries and raspberries, or black fruit such as blackberries or black currents? You will also identify other groups of aromas--spicy, vegetal, gamy, toasted, and milky, to name a few.

Each group of aromas has its own origin. A woody wine was aged in barrels, a Sauvignon wine evokes boxwood or grapefruit, a red wine from the Rhône valley will be spicy with hints of black fruit, while a Bordeaux will smell of strawberries, black current leaves, and pepper. The more you practice, the easier it gets.