CO2 extracts belong to a slightly different category.

Still, they occupy an extremely worthwhile place in the aromatic and therapeutic landscape. Some materials are simply different when extracted this way. Some become more complete. And in a few cases, these extracts would barely exist at all without CO2 extraction technology.

Calendula provides a useful example. Pure Calendula extract — one of the more useful skin-supportive botanical extracts available — cannot realistically be produced through steam distillation. CO2 extraction is what makes the material possible in concentrated form. And this is where things begin to get interesting.

What Is CO2 Extraction?

CO2 extraction uses pressurized carbon dioxide to recover aromatic and oil-soluble compounds from plant material.

When carbon dioxide is placed under pressure and cooled, it becomes liquid. Under even higher pressures, it enters what is known as a supercritical state — behaving somewhere between a gas and a liquid. Think of it as a CO2 “fog.” In this state, carbon dioxide functions as a remarkably clean extraction solvent.

Instead of water vapor carrying aromatic compounds away from the plant — as happens in steam distillation — pressurized CO2 performs that role.

The lower-pressure form of CO2 extraction involves chilling carbon dioxide to between 35 and 55 degrees Fahrenheit and pumping it through plant material at approximately 1,000 psi. Supercritical CO2 extraction involves heating the carbon dioxide to around 87 degrees Fahrenheit and pumping it through at approximately 8,000 psi.

Neither method is universally better. Different parameters are required for each plant, and by further adjusting temperatures and pressures, different varieties of extract can be produced from the same plant material. This is why two CO2 extracts of the same plant may smell and behave differently.

Part Two: How It Changes the Material

Why CO2 Extraction Matters

One of the major advantages of the process is temperature. Many plants contain delicate aromatic compounds, waxes, carotenoids, diterpenes, fatty acids, and heavier lipophilic constituents that are altered or destroyed by high heat. Because CO2 extraction operates at relatively low temperatures, more of these compounds can remain intact in the final extract.

The process is also adjustable. By changing temperatures and pressures, extractors can selectively emphasize different fractions of the plant material.

Summary of Benefits

• Clean: The process can be certified organic, as most CO2 oils and extracts are.
• Cool: Plant material never reaches the boiling point. This preserves compounds that cannot survive steam distillation — and makes possible several extracts that simply cannot be produced any other way.
• Efficient: CO2 carries more lipophilic compounds into the final product without the minor loss inherent in steam distillation. More costly, but you get more from your plant material.
• Adjustable: Temperatures and pressures can be modified to optimize the chemical profile of the resulting extract — producing what are known as Select and Total extracts, explained in Part Three.
• Environmentally sound: Industrial CO2 for extractions comes from byproducts — primarily hydrogen and ammonia manufacturing and fermentation for ethanol. CO2 used for extraction does not contribute to overall atmospheric CO2 levels. The CO2 is recycled after each extraction and used again.
• New options — and sometimes better oils: For some materials, the extraction gives us something genuinely different. Frankincense and Myrrh CO2 extracts are by far the favorites over the steam-distilled oils. They are warmer, smoother, and far more complex.

Part Three: Select vs. Total CO2 Extracts

This distinction causes considerable confusion, and it is worth understanding clearly before exploring specific botanicals.

Select CO2 Extracts

A Select CO2 extract is the closest equivalent to a traditional essential oil. It primarily emphasizes the aromatic fractions of the plant material while also capturing some heavier constituents that steam distillation may leave behind.

Using Frankincense as an example: the Select extract is typically noted as containing 70–85% essential oil, with a high content of alpha-pinene and other monoterpenes including thujene, sabinene, beta-pinene, myrcene, and limonene — along with sesquiterpenes and diterpene alcohols such as incensol and serratol.

Compared to steam-distilled frankincense essential oil, the CO2 Select extract contains a broader aromatic spectrum, including heavier diterpenes and sesquiterpenes such as incensole and incensole acetate. These compounds contribute to the warmer, more resinous profile many people immediately notice when smelling the extract. Typically there are 15–30% more “oil” compounds in the CO2 extract than in the steam-distilled oil, and these are most often heavier, larger molecules not readily carried over by steam.

Frankincense was among the first CO2 extracts to be recognized by clinically oriented aromatherapists worldwide as more therapeutically complete — because of the presence of these larger sesquiterpenes and diterpene alcohols. The same argument applies to Myrrh: the CO2 Select is warm, rich, and deeply resinous in a way that is genuinely worth experiencing.

Total CO2 Extracts

Total extracts attempt to recover nearly all oil-soluble compounds from the plant material — not merely the lighter aromatic fractions. This includes fatty acids, waxes, carotenoids, sterols, and heavier lipophilic compounds.

A Frankincense Total extract, for example, is not produced by any CO2 distiller — one would end up with a gummy mass not much different from the resin itself. But Total extraction is exactly what is called for in cases such as Sea Buckthorn, Rosehip, and Calendula. No steam-distilled version of these materials exists. The higher-pressure Total process extracts all the oil-soluble compounds from these plant materials, and the result is among the most remarkable skin-care ingredients available.

Part Four: The Most Important CO2 Extracts

Which Plants Benefit Most?

Not every botanical improves through CO2 extraction. Lavender, for example, remains excellent as a steam-distilled oil. The CO2 version smells somewhat closer to the living plant, but the therapeutic differences are relatively subtle. Patchouli is another example: some people prefer the aged warmth and oxidation profile of traditional steam-distilled Patchouli over the greener profile of the CO2 extract.

Other materials behave very differently — and a few depend on CO2 extraction entirely.

Frankincense CO2

Frankincense CO2 remains one of the earliest and most respected CO2 extracts in clinical aromatherapy circles. The CO2 extract recovers heavier diterpenes and sesquiterpenes that steam distillation captures less effectively. The result is a warmer, deeper, more resinous aromatic profile that many practitioners feel behaves more like the resin itself. It offers a fuller resin profile than steam distillation alone and is often preferred for topical, meditative, and deeper aromatic work.  

Frankincense is such a useful example of the differences between steam distillation and CO2 extraction that it deserves its own discussion. For a deeper look, see Frankincense CO2 vs. Essential Oil: What's The Difference?

Our owner considers it the foundation of his favorite “therapeutic cologne”: Frankincense Carteri and Serrata CO2, Myrrh CO2, and Indian Sandalwood.

Myrrh CO2

Warm, rich, and resinous in a way steam distillation rarely achieves fully. One of the clearest examples of why resins behave differently under extraction. A very worthwhile experience.

The Spice Oils

Many spice oils develop a fuller aroma with more pronounced middle and lower tones when CO2 extracted. The changes in therapeutic value, however, depend on the specific oil.

Ginger is an excellent example. Steam-distilled Ginger is generally favored for its benefit to the digestive system, whereas the CO2 extraction is richer, warmer, and best used topically for its anti-inflammatory properties. Cinnamon CO2 and steam-distilled Cinnamon are relatively similar, though many people find the CO2 extract somewhat rounder and fuller in aroma.

Calendula CO2

Until CO2 extraction, Calendula was available only as an infusion: one had to soak Calendula flowers in olive oil for months to extract the skin-healing nutrients into the carrier oil. CO2 extraction changed this entirely. A few drops of Calendula CO2 can create a Calendula-rich blend almost immediately. It is one of the more useful skin-supportive botanical extracts available, and one of the clearest demonstrations of what CO2 Total extraction makes possible.

Sea Buckthorn CO2

Dense with carotenoids and fatty acids, Sea Buckthorn CO2 is one of the more remarkable examples of what Total extraction can recover from botanical material. The whole berries contain relatively few volatile aromatic compounds but are exceptionally rich in fatty acids, carotenoids, and other heavier constituents that are highly useful in topical applications. Steam distillation cannot realistically produce this extract. CO2 extraction can, and the result is extraordinary as a skin-care ingredient.

Rosehip CO2

Whole rosehips are rich in deep-red phytonutrients and also contain the oils from the seeds inside. All of these lipophilic compounds are extracted in a CO2 Total. Together with Calendula and Sea Buckthorn, they form a trio of what are, in our estimation, absolute magic skin-care ingredients.

Rosemary CO2

Rosemary CO2 is extracted specifically for its antioxidant fractions rather than its aroma. It is the only known compound to quench every one of the seven classes of oxidative radicals — a remarkable claim, and one worth understanding in context.

EDITOR'S NOTE (2026)

Rosemary CO2 remains widely used as a natural antioxidant in food, cosmetic, and nutraceutical applications. Eric's practical formulation guidance (one to two drops per ounce of carrier oil blend as a natural preservative support) remains sound: small amounts can significantly improve oxidative stability in carrier oil blends while contributing very little aroma. 

German Chamomile CO2

German Chamomile CO2 is often preferred by practitioners seeking a profile closer to the chemistry naturally present in the living plant. The heat of steam distillation converts matricin — a powerful anti-inflammatory compound naturally present in the plant — into chamazulene, the beautiful inky-blue compound familiar in the essential oil. Some practitioners feel the CO2 extract retains a profile closer to the original plant chemistry, before that conversion occurs.

Part Five: When CO2 Makes a Difference

Not Every Plant Benefits Equally

There are many oils that are simply different under CO2 extraction. Not even really therapeutically different — but aromatically different. Patchouli is a perfect example: the CO2 is somewhat green-smelling, like a freshly distilled Patchouli. Patchouli really gets better with age, and while some people enjoy the CO2 aroma, it has not become the preferred form.

Lavender is probably the best example of an oil that is simply “different.” As some linalyl acetate is converted to linalool in the steam distillation process, the plant's natural aroma profile is changed. We do use Lavender CO2 in ingestible formulas, as it is the form found in lavender capsules, though the science does not strongly point to one form being advantageous over the other therapeutically. You may or may not prefer the aroma, and it is certainly worth the experience.

Sandalwood CO2 extracts are only “interesting,” and have not topped the aroma of a good steam-distilled variety — at least not yet.

Truly, there are only a few oils where CO2 extraction produces a materially better product over steam distillation. These can be almost completely summed up in Frankincense and Myrrh, the spice oils, German Chamomile, and the materials where the extract would otherwise not exist: whole Sea Buckthorn Berry, whole Rosehip, and Calendula.

Part Six: Carrier Oils and the Future of CO2

Carrier Oils

One very strong point for CO2 extraction is the extended shelf life of carrier oils produced using this method. Borage Seed and Evening Primrose oils are excellent examples. These are extremely delicate oils, and the cold-pressed varieties require careful attention to keep them away from light and heat. The CO2-extracted varieties are much less susceptible to oxidation. The costs are high — though they are coming down.

The Future of CO2 Extraction

At Ananda, we plan to continue expanding our CO2 offerings and doing our best to explain why you might choose a CO2 over a steam distillate for a particular variety. They are all worth experiencing.

EDITOR'S NOTE (2026)

Since this article was originally written, CO2 extraction has expanded well beyond traditional aromatherapy. The same advantages Eric described — low-temperature extraction, selectivity, and the ability to recover compounds not readily obtained through steam distillation — have led to broader use in skincare, nutraceuticals, natural preservation systems, cannabis extracts, and specialty perfumery.

At the 2025 International Exhibition of Raw Materials for Perfumery in Grasse, France, we encountered aromatic materials produced through advanced extraction methods that were not commercially available when this article was first written, including a true Calendula aromatic extract. These developments do not change the principles Eric outlined here. If anything, they reinforce them. The value of CO2 extraction remains greatest where steam distillation leaves something important behind.

A Final Note

CO2 extraction does not replace steam distillation. It complements it — and for certain plants, it completes it. The extracts that benefit most are the resins, certain spices, German Chamomile, and the materials that would otherwise not exist in concentrated form at all: Calendula, Sea Buckthorn, and Rosehip.

For everything else, the question is not which method is better, but which version best serves your purpose. The CO2 of Lavender and the steam-distilled Lavender are both valid. The CO2 of Patchouli and its aged steam-distilled counterpart are both valid. They are simply different materials, produced differently, with different aromatic characters.

The value of understanding CO2 extraction is not in ranking it against steam distillation. It is in knowing when it changes something important — and when it does not. Readers often ask whether a CO2 extract is “better” than an essential oil. In most cases, that is not the right question. The more useful question is whether the extraction method changes the chemistry in a meaningful way.

— Eric R. Cêch, with editorial notes by Anita Felice (2026)

Archive Restoration Note: This article was originally published as Frankincense CO2 Extracts vs. Essential Oils and has been restored from the Ananda archive with updated formatting, references, editorial notes, and current research context while preserving the substance of Eric R. Cêch's original work.

For educational purposes only. These statements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure or prevent any disease.

Further Reading from the Ananda Apothecary™ Library:

Frankincense CO2 Extracts vs. Essential Oil
Explore why Frankincense became one of the most discussed CO₂ extracts in aromatherapy and how extraction method changes the chemistry of the finished material.

The Three Faces of Frankincense

References

Capuzzo A, Maffei ME, Occhipinti A. Supercritical Fluid Extraction of Plant Flavors and Fragrances. Molecules, 2013. https://pmc.ncbi.nlm.nih.gov/articles/PMC6270407/

Xu L, Tian Y, et al. Recent Advances on Supercritical Fluid Extraction of Essential Oils. https://pdfs.semanticscholar.org/62ef/7a2e5ff023d6b3425aa73994b7cc16ac4a98.pdf

Kamali H, Golmakani MT, Hosseini SMH. Optimization of Lavender Essential Oil Supercritical CO₂ Extraction. Journal of Essential Oil Bearing Plants, 2015. https://pmc.ncbi.nlm.nih.gov/articles/PMC4285650/

Vicente G, García-Risco MR, Fornari T, Reglero G. Supercritical Carbon Dioxide Extraction of Antioxidants from Rosemary. Journal of Supercritical Fluids, 2012. https://pubmed.ncbi.nlm.nih.gov/23196869/

Mihalcea L, et al. CO₂ Supercritical Fluid Extraction of Oleoresins from Sea Buckthorn.
Molecules, 2021. https://pmc.ncbi.nlm.nih.gov/articles/PMC8615056/

Machmudah S, Sasaki M, Goto M, et al. Supercritical CO₂ Extraction of Rosehip Seed Oil.
Journal of Supercritical Fluids, 2007. https://hero.epa.gov/reference/5323517

Rahimi E, et al. Chamomile Extraction with Supercritical Carbon Dioxide.
Journal of Supercritical Fluids, 2011. https://www.sciencedirect.com/science/article/abs/pii/S0896844610004171

Kotnik P, Škerget M, Knez Ž. Kinetics of Supercritical Carbon Dioxide Extraction of Borage and Evening Primrose Seed Oil.
European Journal of Lipid Science and Technology, 2006. https://dk.um.si/IzpisGradiva.php?id=25748&lang=eng

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