What is an aroma?

Aromas are molecular emanations produced by certain plants or animals. They are known as odors, effluvia and perfumes. These aromatic molecules belong to different chemical families: alcohols, aldehydes, ketones, acids and esters. The aromatic palette of these fragrant molecules is so vast and varied that wine professionals have classified them into large families and sub-families. Examples include fresh, dried or candied fruit, fresh, wilted or dried flowers, spices or herbs, etc

The birth of aromas: the grape berry

The grape berry is made up of various components. It is made up of a skin, the pellicle, flesh, the pulp, and seeds, the pips. With the exception of Muscat, which also contains fragrant substances in its pulp, the other grape varieties contain their aromatic molecules in the skin. The skin also contains colorants and tannins. Each grape variety has its own aromatic properties, which it then transmits to the wine. Nevertheless, variations in aromatic intensity and finesse can be observed, depending on a number of factors: climate, soil, grape maturity and yields per hectare.

Aroma development: wine

The many volatile compounds in wine can be perceived in two different ways: through the nose, the odor is perceived, and through the retronasal route, combining the mouth and nose, the aroma is detected. Aromas are also classified into three categories: primary, secondary and tertiary.

Primary aromas are those transmitted by the fruit, the aromatic signature of the grape variety. These aromas vary in intensity, and are classified according to whether they come from "aromatic" grape varieties, such as Muscat or Gewurztraminer, or those that are more discreet, such as Grenache Blanc.

Secondary aromas appear during fermentation. The transformation of sugar into alcohol by yeast releases these aromas, which can take on buttery or milky notes that combine with the primary aromas.

Tertiary aromas develop as the wine matures or ages. They are often reductive (no contact with oxygen) or oxidative (contact with oxygen) in character. As the wine ages, its aromatic range evolves, so a wine with fresh fruit or fresh flower notes in its youth becomes dried fruit or dried flower.