Aromas in wine

As Jean-Paul Guerlain, a legend in the perfume world, said, “A smell is the most intense type of memory”. When it comes to oenology, aromas have an important part to play because they are one of the basic elements for the sensory characterisation of wine. They come from different chemical compounds present in the grapes and in the winemaking process and significantly influence the taste and tasting experience. Here are some simple guidelines to help you recognise the main aromas.

How do you smell a wine?

First of all, we need to know how to smell a wine correctly. Smelling the wine is an important part of wine tasting, because it allows us to identify the different aromas present and therefore better appreciate its flavour. To do this, it is important to use a suitable glass, which has a tulip or balloon shape, and is large enough to give the wine enough surface area in contact with the air. Once the wine has been poured, it should be smelled “still”, which means before swirling it in the glass. Put your nose well inside the glass and inhale deeply to appreciate the first aromas. Then tip the glass on its side to achieve greater volatilisation of the aromas and put your nose back into the glass. There is where other more complex aromas related to winemaking and aging can be appreciated.

How do we classify aromas?

There are a large number of terms to describe olfactory impressions. But although the nuances of a wine’s nose are infinite, in general terms, they can be divided into three main groups:

- Primary aromas

These are the aromas that come directly from the grapes and are inherent to the grape variety used. They are revealed as soon as the wine is poured into the glass and without moving it around. These aromas can be fruity (red fruits, stone fruits, tropical fruits, citrus), floral (rose, lilac, jasmine), vegetal (bell pepper, cut grass, hay, eucalyptus) or mineral (wet slate, granite, pencil point).

- Secondary aromas

These are the aromas that develop during the wine’s fermentation and maceration process. These aromas can be more complex and sophisticated than the primary aromas, and appear when the wine is swirled vigorously. Here we find notes of yeast, toasted bread or brioche, which come from the fermentation, and aromas like yogurt, milk or fresh cheese that come from the transformation of malic acid into lactic acid.

- Tertiary aromas

These are the aromas that develop during the wine’s aging process. It is also known as bouquet and to release these we need to keep swirling the glass with more energy as you taste. These aromas can be woody (cedar, pine, eucalyptus, liquorice), spicy (cinnamon, pepper, vanilla) or empyreumatic (cocoa, toasted bread, nuts, leather).

Other Smells

Finally, we can talk about wine defects we can find through smelling. When the fragrance given off by a wine gives a positive impression, it is called aroma. However, when the fragrance it gives off seems negative, we call it odour. These can directly affect the taste of the wine and you might need to consider opening another bottle. Sometimes these are immediately noticeable, but there are lots of occasions where these defects can be very subtle and difficult to spot. Here are the main ones:

- Cork

If the wine smells corky, it may suggest that the cork used to seal the bottle is defective. This odour is usually musty, and can be very unpleasant. This defect is known as “cork flavour” or “TCA” (trichloroanisole).

- Vinegary

If the wine has a vinegar or acetic acid aroma, it may suggest secondary fermentation in the bottle due to excessive exposure to air or bacterial contamination.

- Oxidised

If the wine smells stale or of old nuts, it may suggest that it has been exposed to oxygen for too long, which has affected its organoleptic characteristics.

- Reduction

If the wine has a sulphur or rotten egg smell, it may suggest that a reduction in fermentation has occurred, which has generated volatile sulphur compounds.

- Poor fermentation

If the wine has a yeasty or blue cheese aroma, it may suggest a bad fermentation, possibly due to low temperature or a lack of nutrients for the yeasts.

It is true that both the aromas and the smells of a wine can be spotted straight away, but working out what they are down to experience. Tasting different wines is one of the best ways to perfect our tasting and smelling skills. Not only will we be able to develop a broader vocabulary to describe the different aromas and flavours, but we will also be able to identify the unique characteristics of each type of wine. Like with everything, practice makes perfect ;)