A Calm, Science-Minded Overview
When you twist open a bottle of essential oil, it feels simple: one plant, one scent, one bottle.
In reality, there’s a whole story between the plant and the bottle — and the way we extract the oil quietly shapes everything from the aroma to the safety profile and price.
At Verdessent, we try to keep one promise: no magic, just clarity. In this first article of our series, we’ll give you a gentle overview of how essential oils are usually obtained, before diving deeper into individual methods in later posts.
What Is an Essential Oil, Really?
In the strict sense, an essential oil is:
A volatile, aromatic mixture obtained from plant material (flowers, leaves, bark, seeds, peels, resins, etc.) by physical processes such as distillation or mechanical expression (like cold-pressing citrus peels).
It’s typically rich in:
- Terpenes and terpenoids (e.g., limonene, menthol, linalool)
- Alcohols, aldehydes, ketones, esters, lactones
- Small amounts of sulfur- or nitrogen-containing compounds
Many of these molecules are sensitive to heat, oxygen, light, and time. That’s why the extraction method matters so much: a gentle process can preserve delicate notes; a harsh one can flatten or distort them.
The Main Families of Extraction Methods
Most essential oils used in aromatherapy or perfumery are obtained by one of these broad method families:
- Water-based distillation
- Hydrodistillation (water distillation)
- Steam distillation
- Solvent-based extraction
- Classical solvent extraction
- Variations that produce concretes and absolutes
- Pressure & phase-based methods
- Vacuum distillation
- Supercritical CO₂ extraction
- Modern “assisted” techniques
- Ultrasound-assisted extraction
- Microwave-assisted water distillation
- Other hybrid or assisted methods
In this first article, we’re just mapping the landscape. The next posts will zoom in and ask: What does each method do to the oil? What are its strengths and limitations?
Why the Method Matters
The extraction method can influence:
- Aroma profile
Some methods emphasize light, fresh top notes; others pull out heavier, waxier components. - Chemical composition
Heat, water, pressure, and time all nudge the balance of molecules in subtle (and sometimes not-so-subtle) ways. - Stability and shelf life
Oils that undergo harsh processing or contain more oxidizable compounds may age differently. - Safety & purity
Solvent-based methods, for example, must be carefully controlled to avoid residual solvent in the final product.
So when you see “steam-distilled,” “CO₂ extract,” or “absolute” on a label, those are not just marketing terms — they are clues about how the plant’s aromatic world was brought into your bottle.
How This Series Is Structured
To keep things clear and calm, this series is broken into four short articles:
- This overview – the map of the territory.
- Classic distillation methods – hydrodistillation, steam distillation, and what they mean for your oil.
- Solvent & CO₂ extracts – where they shine, and how they differ from “standard” essential oils.
- Modern “gentle” techniques – especially microwave-assisted water distillation, and why researchers are excited about it.
We won’t tell you that one method is magically “best” for everything. Different plants and different uses sometimes call for different tools. Our goal is simply to help you read labels with less confusion and more confidence.
In the next article, we’ll start with the classics: hydrodistillation and steam distillation — the quiet workhorses behind many of the essential oils you already know.