Primary, Secondary and Tertiary Aromas: Can You Recognise Them?

Aromas are a group of volatile compounds made up of aromatic molecules. It is precisely because these compounds are volatile that they reach our olfactory receptors.

There are very simple and much more complex sets, with some aromas being made up of thousands of volatile compounds. In order to simplify the tasting process, these smells are associated with aromas that we already know. This is why we talk about different fruits, flowers or mushrooms when tasting wine.

Aromas are the essential part of the olfactory tasting process, the "nose" of wine, but they also play an essential role in the tasting process, the "palate" of wine. Learning to distinguish between the aromas perceived by the nose and the palate is probably one of the most difficult steps in wine tasting. An aroma is the sensation perceived by the sense of smell: to be distinguished from flavours which are perceived by the tongue. It takes time and practice to be able to identify them successfully. This requires regularly familiarising your nose with the different existing aromas and flavours. Only with time will our nose become more refined and able to identify more aromas.

But where do the aromas in wine come from? The aromas can be distinguished into three groups: primary, secondary and tertiary aromas. The primary aromas come from the grape variety itself, the secondary aromas from the production process and the tertiary aromas appear with ageing.

While primary aromas come from the fruit itself, secondary aromas come from the production processes including fermentation, malolactic fermentation and lees ageing. Fermentation is the crucial stage in the wine making process where sugars are converted into alcohol. The types of yeast, ferments, fermentation conditions and temperatures are factors that contribute to the variety of secondary aromas.

They fall into three distinct groups:

• fermentative notes such as breadcrumbs, brioche, yeast or biscuit
• dairy products such as butter, yoghurt, milk, of course, or caramel
• amylics with flavours like liquorice, nail varnish and bananas

Banana aromas, which are often present in new wines such as Beaujolais or in certain very young white wines, are mainly the result of a specific fermentation technique called carbonic maceration. In short, the conditions under which fermentation takes place have a direct effect on the synthesis of secondary aromas, and the winemaker can choose whether or not to intervene in this process.

The key to successful winemaking is to find a good balance between each of the aromatic groups: primary, secondary and tertiary. In fact, too many secondary aromas can hide the terroir and the primary aromas of the grape variety.