Infusion

What is infusion?

In perfumery, the infusion technique consists of letting flowers or plants steep in a boiling liquid. This method is comparable to that of a tea infusion. The idea is to extract the aromas of a plant through their dissolution in a liquid that is initially heated and then left to cool. This operation is the opposite of decoction, in which the liquid is kept boiling. However, while making tea only requires the use of water, in perfumery the method is quite different. The solvent used is not necessarily water. It may be oil or alcohol. This technique proves to be particularly costly and is intended for extracting olfactory elements from dry materials such as vanilla pods. The latter is brought into contact with a solvent liquid and placed in a vat brought to a boil. The mixture is then cooled and kept that way for a minimum period of six months. As one will have understood, infusion proves to be a technique that requires patience as well as a large storage space, hence its high cost. This is why it is a craft that is very little used today.

Plants suited to infusion

Despite its extreme simplicity, infusion remains a technique that must be properly mastered for it to be effective. Moreover, not all plants are good for infusing. The fragrant part of the plant must be fragile enough to release its identity upon contact with the heated substance. In general, most stems and leaves as well as flowers are perfectly suited to infusion, which is not always the case for some fragrant roots or more solid materials such as barks. Overall, infusion is suited to plants that are rich in volatile, subtle and aromatic substances. What is more, decoction cannot be used on this type of plant, because too high a temperature for too long would destroy their odorous components.

Nowadays, infusion is reserved more for herbal tea enthusiasts than for perfume makers. Nevertheless, this technique is undeniably part of our heritage and constitutes one of the oldest crafts in the olfactory sector. Having emerged in antiquity, it has endured into our modern era and stands as excellent testimony to the beginnings of perfumery as we know it today.