Essential Oil Storage for Keeping It for as Long as Possible.

Essential oils are mainly used in phytotherapy and aromatherapy. An essential oil is characterized by the Latin name of the plant used for its extraction, its geographical origin, its method of cultivation and the part of the plant used to obtain it. Although there are several processes for extracting essential oils from aromatic plants, low-pressure steam distillation is the most common technique for extracting essential oils from plants.

In cosmetics, essential oils can be used in skin and hair care products. Some are also used in perfumery. Every so often an essential oil is used solely to perfume a care product or mask the scent of another component, but it is quite possible for it to be added to the formula for its action on the skin or hair. There are almost as many cosmetic benefits as there are essential oils.

Essential oils are different from vegetable oils in the way that they do not contain fatty acids. They are also strongly contraindicated during the first three months of pregnancy.

As a general rule, essential oils can be stored for between three and five years. This period varies according to factors such as the quality of the original plant, harvesting conditions, distillation method and bottling process. Citrus essential oils have the shortest shelf life (three years maximum), as they tend to oxidize more quickly. Sensitive to the sun's UV rays, essential oils are usually packaged in amber bottles to prolong their shelf life. There are several steps you can take at home to protect essential oil and its quality.

• The best way to store essential oils is in a compartment protected from light and heat (ideally between 5 and 30 °C), to minimize oxidation.

• Write the opening date of the essential oil on the bottle. If you notice a change in smell or appearance, do not use the essential oil.

• To protect essential oil droppers and caps, always place bottles upright.

• As far as possible, try to limit contact between your skin and the dropper tip of the bottle, so as not to contaminate it. Instead, pour drops of essential oil directly into your hands.

Note: Some essential oils are combined with vegetable oils, making them particularly sensitive to oxidation. This type of blend can be kept for 6–8 months after opening, in a cool place such as the refrigerator.

• FAUCON M. Traité d'aromathérapie scientifique et médicale - Les huiles essentielles - Fondements et aides à la prescription (2017).