What is an aromatic hydrolat?
A hydrolat is the aromatic water produced during the distillation of plants (aquae distillatae ex plantis).
Hydrolats are obtained by distilling the various parts of aromatic plants with steam. They form during condensation and are separated from the essential oil (when present).
For some time, hydrolats were falsely believed to be a residue of distillation. Today, they are praised as outstanding cosmetic treatments.
Hydrolats are not to be confused with floral waters
Floral waters are obtained by soaking flowers in purified water or by way of steam distillation followed by decantation and filtration. Hydrolats are not the same as they are produced in an extremely different manner.
Given the lower concentration of biochemals in hydrolats, we cannot expect them to have the same “molecular” properties as essential oils. They are, however, extremely beneficial for the skin and its mucous membranes.
The history of hydrolats
- 4th century: Synesius of Ptolemais and Zosimos of Panopolis provide detailed descriptions of Egyptian distillation devices in their writings.
- 6th century: Aëtius of Amida, a doctor and writer living in Constantinople, describes empyreumatic distillation by hydrodiffusion.
- 8th to 11th century: Arab scientists develop distilled waters from rose and absinthe. Doctors such as Nonus Theophanes, Serapion, and Avenzoar recommend hydrolats as remedies.
- 15th century: After the Crusades, the West takes over and hydrolats become the main purpose of distillation. Jean Winther, professor of medicine in Strasbourg, moves distillation from the laboratories of alchemists to the laboratories of pharmacists.
- 16th century: the book “New Gross Destillirburch” provides many details about distillation devices and the production of hydrolats and their healing power.
- 1880: hydrolats are mentioned in the “Traité de la pharmacie galénique” (“Treaty on galenic pharmacy”). The use of fresh plants was preferred to that of dried plants because they keep longer. Fresh plants create a more transparent hydrolat and their aroma is always sweeter and more developed.
- 1942: in volume 1 of “Pharmacie galénique” (“Galenic pharmacy”) by A. Gomis and A. Liot, further details are provided:
Producing an aromatic hydrolat
All aromatic hydrolats are produced by the steam distillation of aromatic plants harvested at a specific moment of their growth cycle. A product that is obtained in any other way than distillation cannot be considered an aromatic hydrolat.
Farmers and distillers must strictly adhere to the specifications for the production of hydrolats and ensure that these delicate water-based products remain as pure as possible.
During the steam distillation process, aromatic hydrolats are usually extracted for an hour to ensure they capture the full richness and fragrance of the distilled aromatic plant. Sometimes the extraction continues for much longer (3 to 4 hours) to optimize yields, but in such a case the product will be much less effective than an authentic and concentrated hydrolat and therefore not as suitable for therapeutic treatments.
Unlike essential oils obtained by the same extraction process, aromatic hydrolats contain a variety of different molecules in addition to aromatic and terpene molecules.
In fact, the steam extracts other active hydrophilic ingredients that are found in the hydrolat. The composition of an aromatic hydrolat is therefore particular and unique.
The quality of hydrolats
Consumers are presented with a huge selection of essential oils and aromatic hydrolats, some of which are better than others. Here are a few tips to help you choose the highest-quality products.
Only one term is correct: aromatic hydrolat. In fact, only aromatic hydrolats are 100% derived from steam distillation. Be wary of “hydrosols,” “floral waters,” and “aromatic waters” as these items open the door to products that simply emulsify or solubilize essential oil or dilute an aromatic hydrolat with water. NOTE: In the United States, the word ‘hydrolat’ is not recognized and we call our hydrolats “hydrosols”.
AHCT or ChemoTyped Aromatic Hydrolat
Today’s technology allows us to identify and quantify all the molecules contained in an aromatic hydrolat. Among other things, this technology provides us with foolproof evidence regarding the properties of hydrolats and knowledge of their molecular concentration and biochemistry.
A AHCT hydrolat always presents a higher concentration than any other hydrolat that is collected during the distillation process. Chemotyped aromatic hydrolats are collected at a precise moment during the extraction by distillation process.
As aromatic hydrolats have no preservatives, these liquids are delicate quickly become contaminated if mishandled.
Produced by steam distillation, hydrolats are sterile upon exiting the alembic. Nevertheless, they can still become contaminated by unsanitary containers or operators. The most common conservation method is microfiltration (0.2 microns), which takes place before the hydrolat is packaged in glass vials (ideally) or any opaque container. Storing aromatic hydrolats in the refrigerator will help them last longer.
In the right conditions (proper distillation, handling, microfiltration, packaging that protects the product from light and oxygen), a hydrolat will last for more than 2 years. However, once a bottle is opened, it can only be used for 6 months as the liquid can quickly become contaminated.
Aromatic hydrolats are usually sold as sprays in glass bottles, but the Pranarôm laboratory recommends the use of a spray bomb that optimizes quality by using an airless system with no propellant. These systems prevent hydrolats from becoming contaminated and considerably extend their shelf life.