Enfleurage

Enfleurage is a process that uses odorless fats that are solid at room temperature to capture the fragrant compounds exuded by plants. The process can be "cold" enfleurage or "hot" enfleurage.

There are two types of processes:

In both instances, once the fat is saturated with fragrance, it is then called the "enfleurage pomade". The enfleurage pomade was either sold as it was, or it could be further washed or soaked in ethyl alcohol to draw the fragrant molecules into the alcohol. The alcohol is then separated from the fat and allowed to evaporate, leaving behind the absolute of the botanical matter. The spent fat is usually used to make soaps since it is still relatively fragrant.

The enfleurage fragrance extraction method is by far one of the oldest. It is also highly inefficient and costly but was the sole method of extracting the fragrant compounds in delicate floral botanical such as jasmine and tuberose, which would be destroyed or denatured by the high temperatures required by methods of fragrance extraction such as steam distillation. The method is now superseded by more efficient techniques such as solvent extraction or supercritical fluid extraction using liquid carbon dioxide (CO₂) or similar compressed gases.

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