Extracting Fragrance From Flowers: A Beginner's Guide

Extracting fragrance from flowers is a simple process that can be done at home. There are several methods to extract fragrance, including steam distillation, solvent extraction, enfleurage, and maceration. Steam distillation involves passing steam through the flower material, causing the volatile aroma compounds to evaporate and then be collected. Solvent extraction uses a solvent such as hexane or ethanol to dissolve the aromatic compounds, which are then separated from the solvent. Enfleurage involves placing flower petals on a layer of odourless fat or oil, which absorbs the aroma compounds over time. Maceration involves soaking flowers in a carrier oil to extract the fragrance. These methods can be used to extract fragrance from a variety of flowers, including roses, lilies, lavender, jasmine, and orchids.

Using oil to extract fragrance

Selecting Flowers

Almost all flowers should provide a result, but for some, the fragrance might be very faint. You can pick your favourite flower or try a herb. Some flowers that work well are roses, lilies, and carnations. Blooms that are just beginning to open contain the most fragrance. Avoid flowers that are in full bloom as their scent will have begun to fade.

Preparing the Petals

The important parts of the flower are the petals, so pull those off and use your fingers, or a pestle and mortar, to crush and bruise them before putting them into a jar or a zippered food storage bag. If using a bag, seal it and tap it lightly with a wooden mallet to bruise the petals and release the fragrance oils. Make sure you cram as many petals into your jar as you can.

Adding Oil

Now, add a known volume of oil to the petals. Olive oil is an inexpensive oil that works well as a carrier oil. Other options include corn oil, sesame oil, or sweet almond oil, which adds a pleasing, distinctive fragrance of its own. Add enough oil to cover all the petals, then stopper the jar and give it a good shake to ensure that all the petals are covered in oil and that the oil-flower mixture is properly mixed.

Leaving the Mixture

Seal the bottle and leave it somewhere dark for 24 hours. After this time, the scents from the flowers should have been fully absorbed by the oil.

Draining and Straining

After 24 hours, remove the jar from the dark and take off the lid. Use a strainer to drain the flower petals, collect the oil in another container, and then use a spoon to press down on the petals against the strainer so that you can collect as much of the flowery scented oil as possible.

Storing the Oil

Store your fragrant oil in a glass bottle in a cool, dry place. Use it in potpourri or crafts, or wear it as a perfume.

Using water to extract fragrance

Water can be used in various ways to extract fragrance from flowers. One common method is through distillation, which involves passing steam through the flowers to condense the fragrant compounds into water and oil. This technique is often used for flowers like orange blossoms and roses.

Another way to use water for fragrance extraction is through a process called enfleurage, which involves placing flowers in a dish with fat or oil, covering them with a glass pane, and leaving them in the sun. The flowers need to be replaced daily, and the process can take several days to capture their scent. While this method may not produce as strong of a scent as distillation, it is still effective and has been used traditionally.

Additionally, you can create infused waters by boiling or simmering flowers in water to release their fragrance. This method is simple and can be used to create floral waters or hydrosols, such as rose water or lavender water, which retain some of the fragrant compounds from the flowers.

It is important to note that water is not the only solvent used in these processes, as other substances like oil or alcohol may also be involved. However, water plays a crucial role in diluting and extracting the fragrant compounds from the flowers.

The specific steps for using water to extract fragrance from flowers may vary depending on the method chosen and the type of flowers used. Each technique has its advantages and considerations, and some methods may be more suitable for certain types of flowers than others.

Steam distillation

The process involves passing steam through the flower material, which causes the volatile aroma compounds to evaporate. The steam and essential oil vapour are then condensed and collected separately. This method helps preserve the delicate aromatic compounds present in some flowers, resulting in high-quality essential oils with the true and characteristic scent of the flower.

To begin, the flowers or plants are placed on a perforated tray located at the upper part of a tank. If using roses, the petals are covered with water. The mixture is then boiled, and the rising vapour released is impregnated with the fragrant principles of the flowers. This vapour is carried through a coil, where a refrigeration system allows it to condense.

The liquid obtained is a mixture of essential oil (or essence) and water. Since oil and water do not mix due to their different densities, they will naturally separate, with the oil floating to the top for easy collection. The water collected from the condensate, known as hydrosol or floral water, retains some of the fragrant compounds and is often used in cosmetics and other products.

The speed and duration of the steam flow are important considerations, as too much steam may alter the aromatic components or dilute the concentration of flower water. The cooling pipes used to condense the vapour should be maintained at a temperature of 4 to 10°C to ensure effective liquefaction.

Solvent extraction

To begin the process of solvent extraction, the raw materials are submerged and agitated in a solvent that can dissolve the desired aromatic compounds. Commonly used solvents for this process include hexane, diethyl ether, benzene, and petroleum. This mixture is then placed into a rotating drum. The solvent dissolves the plants, leaving behind a waxy substance known as a "concrete" that contains the oils, waxes, resins, and other lipophilic (oil-soluble) plant material.

The next step involves removing the solvent from the concrete for re-use. This can be done through vacuum processing or a lower-temperature distillation process. The remaining waxy mass, or concrete, is then mixed with another solvent, often ethyl alcohol, which only dissolves the fragrant low-molecular-weight compounds. This mixture is then distilled a second time, separating the alcohol from the absolute—the fragrant oil.

The absolute produced through this process may be more faithful to the original scent of the raw material, as it is not subjected to high heat during the distillation process. This method is commonly used for flowers such as jasmine and rose, yielding extremely fragrant extracts.

Enfleurage

Cold Enfleurage

Cold enfleurage uses a large framed glass plate, called a chassis, which is smeared with a layer of animal fat, usually lard or tallow, and allowed to set. Botanical matter, usually petals or whole flowers, is then placed on the fat and its scent is allowed to diffuse into the fat over the course of 1–3 days. The process is then repeated by replacing the spent botanicals with fresh ones until the fat has reached the desired degree of fragrance saturation. This procedure was developed in southern France in the 18th century for the production of high-grade concentrates.

Hot Enfleurage

In hot enfleurage, solid fats are heated and botanical matter is stirred into the fat. Spent botanicals are repeatedly strained from the fat and replaced with fresh material until the fat is saturated with fragrance. This method is considered the oldest known procedure for preserving plant fragrance substances.

Post-Enfleurage

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 was 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.

Advantages of Enfleurage

Disadvantages of Enfleurage

The enfleurage method is highly inefficient and costly and has been superseded by more efficient techniques such as solvent extraction or supercritical fluid extraction.

Frequently asked questions