Olfactory Examination
How to taste a Cognac Olfactory Examination 
The considerations above lead us to pay particular attention to the olfactory examination. Frequently during the production process the master blender will stop his tasting at this point. For distillates at high strength this does not really represent a privation. The vast majority of Cognacs on the market contain 40% alcohol by volume, occasionally a little more, and one of major difficulties in tasting is that of "ignoring" the violence of this alcoholic backbone which provides the support for the various aromas which the taster must try to identify. The quality of the product depends on the number and the subtlety of these aromas.
One of the best known brokers in the Cognac industry offers some sensible advice on this phase of tasting, always maintain a small gap between the nose and the glass, devote an equal amount of time to each sample and this without inhaling in an exaggerated manner. The reason is simple and we have mentioned it previously, the aggressive nature of the alcohol.
As for wine one should avoid swirling the liquid in the glass before the first nosing as this may eliminate the most volatile aromas, it should however be used for the following nosing.
A third nosing is often used following the addition of a small quantity of water. This water, used historically to make a "fine à l'eau" in France and widely employed in Asia serves as catalyst for aromas, its effect for fruity and floral notes in freshly distilled spirit in Cognac can be spectacular. One often speaks of wines which are "closed", our experience tells that spirits will also benefit from some time in the glass to open up and quality Cognac will continue to evolve, as do top wines, and this until the often neglected pleasure of the empty glass. Care must however be taken with old bottles which do not always react well to contact with air and whose noses can be fleeting.
A careful nosing phase will provide a great deal of information. Cognac contains an aromatic complexity which is enviable and envied by many. We can find notes from numerous aromatic families; fruity, floral, woody, spicy, grilled, vegetal…..etc.
It is the search for and the decoding of these complex messages which furnish the real pleasure for a Cognac lover.
The BNIC (Bureau National Interprofessionnel du Cognac) has creared two charts that might help to understand your sensations and to find the right words to discribe them :
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Les Caracteristiques Aromatiques du cognac (in french)
Younger blends will be characterised by fruity and floral notes with perhaps a touch of dry hay and vanilla.
With more prolonged ageing we will find spices and dried fruit and in a Cognac XO of good standing it will the "rancio charentais" which dominates.
This term is untranslatable in many languages and notably in English. It describes the complexity and volume produced by the controlled and gradual oxidisation of the aromatic components contained in the base spirit combined with those extracted from the oak barrels all of which are further concentrated by the evaporation which occurs naturally. In turn we can find dried fruit, walnuts, hazelnuts, oak and vanilla, traces of leafy humus, floral notes such as iris and jasmine, spices such as pepper and cinnamon. If the taster wishes to go further he can look for the influence of "crus" , the barrels and the type of cellaring and even the distillation.
For this memorisation is vital and pushes us to work as hard as possible to build up our references.
Glossaire: Emile Peynaud & Jean Ribéreau-Gayon - anciens professeurs de "l'Institut d'œnologie" de Bordeaux.
fine à l'eau – Cognac mixed with water
closed – a wine or spirit whose aromatic qualities seem difficult to attaincrus – viticultural regions which are identified for certain product characteristics
oxidisation – the chemical change caused by the combination of oxygen with other elements
