Natural Oils in Perfumery and Skincare: A Guide to Essential and Carrier Oils

When we talk about natural oils, we are actually referring to two entirely distinct families. One carries the scent; the other carries the one that carries the scent. Without grasping this distinction, neither a safe blend nor a balanced formula can be achieved.

Essential oils (fragrance oils in the essential sense) are highly concentrated extracts that contain a plant's aromatic molecules in abundance and evaporate at room temperature. Lavender, thyme, tea tree, and eucalyptus all belong to this family. When dropped onto paper, they disappear without a trace — because they are made up of light, small molecules.

Fixed (carrier) oils are non-volatile, oily-textured oils obtained by cold-pressing plant seeds and kernels. Jojoba, sweet almond, apricot kernel, and grapeseed all belong to this family. They leave a permanent oily mark on paper. Their role is not to smell but to dilute essential oils and deliver them to the skin.

The same two families serve different purposes on different stages. Let us first distinguish what they do, then move on to how to use them.

Essential oils in perfumery form the natural heart and some of the top notes of a fragrance. Citrus oils (bergamot, lemon) provide the fast-fading top note; lavender, rose, and ylang carry the heart; while vetiver, sandalwood, and patchouli anchor the base. Bear in mind, however: longevity depends not only on proportion but on the volatility of the raw material itself. A citrus-heavy formula will dissipate quickly even at a high concentration; a resinous, high-molecular-weight formula can linger at a low concentration.

Carrier oils in perfumery primarily serve as the vehicle in oil-based (alcohol-free) perfumes and roll-on applications. Jojoba is the favourite here because it is technically a liquid wax, resistant to oxidation, and leaves no greasy film on the skin.

In skincare, essential oils are added for their aroma and traditional uses; carrier oils provide the base for moisturisation, massage slip, and skin-barrier support.

Dilution in perfumery is not a luxury — it is a necessity. Essential oils are extremely concentrated; they must always be incorporated into a base before coming into contact with the skin.

The general principle is this: essential oils are never applied neat to the skin. They are reduced to the desired percentage in a carrier oil. The percentage is calculated relative to the total blend.

Grams or millilitres? Building your formula by weight (g) is the safest approach, because the specific gravity of oils varies: citrus oils are approximately 0.84 g/ml, while some heavy synthetics or resins can exceed 1.10 g/ml. Working exclusively in ml can lead to overflow or shortfall during bottling. Use a precision scale (0.01 g) and factor in density when converting to ml.

Blending the right oil at the right ratio is half the work; the rest comes down to application and storage.

Massage and skin: Warm the diluted blend in your palms and apply in a thin layer. Carrier oils absorb at different rates — jojoba and grapeseed are light and fast-absorbing; avocado and olive are heavier and absorb more slowly. Choose a lightweight carrier for oily skin and a rich one for dry skin.

Diffuser: A few drops of essential oil in the water reservoir is sufficient. Going overboard does not improve the scent — it simply weighs the air down.

Shelf life: Essential oils, especially citrus, oxidise on contact with oxygen and their scent turns. Carrier oils go rancid (turn bitter). Store both in dark, cool, tightly sealed glass bottles. You will recognise a rancid oil immediately by its smell — do not use it.

A "natural" label does not automatically mean safe. Safety depends not on the source but on the molecule and the level of use.

The "natural = safe" fallacy: The strictest IFRA restrictions most commonly apply to molecules found in natural oils (citral, eugenol, oakmoss). Natural bergamot and other citrus oils are phototoxic — if skin to which they have been applied is exposed to sunlight, permanent pigmentation and burns can result. By contrast, some pure synthetics are virtually neutral from an allergy standpoint. What matters, therefore, is not the name but what the substance is and how much is used.

IFRA and compliance: Limits are set not on the total ratio but on the individual substances present and the product category (leave-on / rinse-off). Always read the IFRA/compliance declaration for the oil you are working with.

If you are moving to production scale, note that on the cosmetic product notification side, the process (notification steps) and responsibility (responsible person/manufacturer obligations) are separate items; company registration and product notification are subject to official fees. Refer to the TİTCK as the authoritative source for current procedures.

To explore the full range of essential and carrier oils — with specification details and usage ratios — browse the Natural Oils category on esans.com.tr. Fresh-aromatic notes such as thyme, tea tree, and eucalyptus make a solid starting point for the first accord you build. The rest is your signature.