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Thyme

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COMERG • Thyme extraction

Sweet Thyme

Thymus vulgaris L. ct. geraniol

Turn thyme into a softer, sweeter food-grade extract with COMERG equipment. This is the geraniol chemotype of thyme, rosy and rounded rather than sharply medicinal. Our cold, room-temperature, low-pressure process captures that gentler character intact, without the heat that flattens it.

Geraniol chemotype, the gentle, rose-sweet side of thyme
Technical reply in 48h Free yield review Worldwide shipping
21% geraniol

The herb

Not the thyme you expect

Common thyme, Thymus vulgaris, comes in several chemotypes, plants of the same species that build different oils depending on where and how they grow. Most thyme on the market is the hot, medicinal thymol type. This one is the geraniol chemotype, sometimes called sweet thyme, where rosy, gently citrus geraniol leads the profile.

The result is a thyme that is rounder and softer on the nose, the herbal backbone still there in the thymol and carvacrol underneath, but lifted by a sweet, floral top. It is harvested as stems, milled and processed cold so that delicate geraniol is never driven off.

Raw material

Botanical nameThymus vulgaris L.
ChemotypeGeraniol
FamilyLamiaceae
Plant partStems
OriginBulgaria
AvailabilityAll year

The extract

What the process delivers

Run on COMERG equipment, thyme stems yield a standardised, true-to-chemotype extract, batch after batch. The cold, solvent-light cycle is what keeps the rosy geraniol top in balance with the herbal phenols underneath, rather than cooking it away. The figures below are typical of a standardised BThy-50.1 grade.

≥50%Volatile oil v/w
21%Geraniol
0.23DPPH IC50 mg/ml
<25 °CExtraction temp
97%Compound recovery
~375 kgHerb per kg extract

The method

Cold extraction, in three steps

No heat, no leftover solvent. This is what happens inside a COMERG aerosol system, and why the chemotype stays true in the bottle.

1

Pressurised R134a flooding

Non-toxic liquefied R134a gas is introduced to the milled thyme at controlled, low pressure. There is no heat, the cycle begins and stays at room temperature.

2

Selective aromatic dissolution

The liquid gas gently dissolves the geraniol, the geranyl acetate and the herbal phenols together, so the sweet top and the savoury base come across in their natural ratio.

3

Recovery and pure extract

The R134a is fully recovered and recycled in a closed loop. What is left is a concentrated thyme extract, at least 50% volatile oil, with under 0.1 g/kg residue.

Aromatic profile

A profile led by geraniol

This is what marks the chemotype out. In a standard thyme, thymol would top the chart. Here geraniol leads, with geranyl acetate and linalool adding to the sweet, rounded character, and thymol and carvacrol giving the herbal depth. Principal constituents above 1%.

Geraniol
21%
Thymol
15%
Carvacrol
10%
Geranyl acetate
7%
Linalool
7%
Germacrene, beta-bisabolene
5%
p-Cymene
5%
beta-Caryophyllene
3%
0%10%15%21%+

Other extractables present. Per-batch GC-MS report available on request.

Specification

BThy-50.1 at a glance

Identity & origin

Botanical nameThymus vulgaris L.
Plant partStems
OriginBulgaria
Product codeBThy-50.1
CAS No.84929-51-1
EINECS No.284-535-7

Production

MethodLiquefied-gas extraction
TemperatureBelow 25 °C
SolventFood-grade (Dir. 97/60/EC)
Solvent residue< 0.1 g/kg
StandardisationDeclared volatile oil
Concentration1 kg ≈ 350-400 kg herb

Physical

AppearanceDark green viscous liquid
Volatile oil50-55% v/w (ASTA)
INCI nameThymus Vulgaris Extract
Density950 g/l
Refractive index1.4922
Acid value11.9 mg KOH/g

Solubility & output

In oilsFully soluble
In 40% alcoholPartial
In waterInsoluble
Flash point> 61 °C
TransportDangerous good (ADR)
Shelf life2 years

Why this thyme, why cold

A gentle chemotype, captured whole

A rare chemotype

Thymus vulgaris ct. geraniol, Bulgaria

Lead compoundGeraniol, not thymol
Herb per kg extract~350-400 kg
Volatile oil≥ 50% v/w
AntioxidantDPPH IC50 0.23 mg/ml

Captured cold

Versus steam distillation

GeraniolRosy top kept
Thymol, carvacrolBalanced, not harsh
Process temperature< 25 °C
Chemotype ratioPreserved

Applications

What you can make

Food & flavour Meat & savoury Fine perfumery Skincare & cosmetics Natural antioxidant Home fragrance

The softer geraniol profile makes this thyme easier to work into delicate formulas than a sharp thymol oil. The extract can be taken concentrated or diluted in a carrier oil to suit the application. Typical filling rates for the concentrated extract in food are 1 to 100 mg per kilogram of product.

Why the COMERG line

Built to keep a chemotype true

The balance that makes this thyme special is fragile, and prolonged heat is what usually breaks it. Our line is engineered around the things that matter when the exact ratio of compounds is the product.

Room temperatureR134a aerosol extraction works cold and at low pressure, so the delicate, volatile geraniol top is never driven off.
True to the chemotypeThe natural ratio of geraniol to thymol and carvacrol comes through unchanged, so the extract really is sweet thyme.
Fully automatedClosed-loop systems run the cycle for you, so results stay consistent and one operator can handle the line.
Fast cycles, high yieldLow-pressure extraction is quick and recovers up to 97% of the herb's compounds, more than older high-pressure CO2 lines.
Scales with youFrom a 10 l pilot unit to 2000 l production, the same method grows from R&D batches to full output.
Clean and economicalIt uses around 85% less energy than solvent methods and needs no special hazardous-location facility.

Why it wins

Compared to the alternatives

Against steam distillation, solvent and CO2, cold R134a extraction keeps the chemotype intact, with a clean, true result.

FeatureCOMERG R134aSteam distillationSolventCO₂ supercritical
Process temperature< 25 °C (room temp)100-150 °C40-70 °C31-80 °C
Aromatic preservation95%+60-75%~85%~80%
Compound recoveryup to 97%70-85%80-90%85-92%
Geraniol top noteKept in balancePartly lost to heatRetainedMostly retained
Solvent residue< 0.1 g/kgNoneNeeds post-purgeNone
Energy use85% less vs solventHighMedium-highVery high
Special facilityNot requiredNot requiredRequiredHigh-pressure safety

From herb to extract

The machines for thyme

A complete COMERG line takes thyme from raw herb to a finished extract. These are the core stages, each available as standalone equipment.

View all equipment
Product specificationFull composition, properties, packaging and handling for thyme extract BThy-50.1.
Download PDF

Questions

Thyme extraction, explained

A 100% natural thyme extract, product code BThy-50.1, from the geraniol chemotype of Thymus vulgaris. It reaches at least 50% volatile oil, led by around 21% geraniol, with no additives.

Thyme of the same species can build different oils depending on where it grows. This batch is the geraniol type, sweeter and rosier than the common thymol type, which makes it gentler to formulate with while keeping thyme's herbal character.

Liquefied food-grade gas extraction at room temperature, below 25 °C, and low pressure. Because there is no high heat, the delicate aromatic compounds are preserved and solvent residue stays below 0.1 g/kg.

Roughly 1 kg of extract represents around 350 to 400 kg of dried, milled thyme.

Yes. The same cold process runs from a 10 l pilot unit to 2000 l production systems, so you can start small and grow without changing method.

It is produced with a food-grade solvent per Directive 97/60/EC. It is a raw material for formulation, not intended for direct consumption or undiluted topical use, and users are responsible for compliance with applicable legislation.

Yes. A per-batch GC-MS analysis is available on request, and a Safety Data Sheet per 2006/1907/EC is supplied with the product.

Set up your thyme line

Tell us your throughput and target product. We will recommend the right system, share a yield estimate for your thyme, and reply with pricing and lead time, usually within 48 hours.

COMERG extracts are raw materials for product formulation. They are not intended for direct consumption or for undiluted topical application in cosmetics, perfumery or aromatherapy. This information is provided to the best of our knowledge and is not a substitute for prior testing of suitability for the intended use. Keep away from children.

The thyme line

Equipment for processing thyme

The machines below make up the thyme line, the equipment that takes the herb through to a finished extract. Request a quote on any unit and we will reply with pricing and lead time.

  • 5L Fully Automated Compound Remediation System

    5L Fully Automated Compound Remediation System

    A bench-scale system that refines a finished botanical extract, selectively removing unwanted constituents at room temperature while preserving the aromatics and actives.

  • 6" SS Wiped Film Distillation System

    6″ SS Wiped Film Distillation System

    A stainless-steel short-path wiped film system that distills and purifies heat-sensitive botanical fractions in seconds under deep vacuum, with no thermal damage.

  • Automated Vape Cartridge Filling Machine

    Automated Vape Cartridge Filling Machine

    A compact automated filler for viscous botanical oils, with a heated mixer, jacketed feed and temperature-controlled nozzle for clean, bubble-free 0.3-3 mL doses.

  • Dual-Cut Botanical Harvester

    Dual-Cut Botanical Harvester

    A tractor-towed harvester that cuts flowering tops and stalks in a single pass, feeding a self-unloading 5 m³ bunker at up to 2 hectares per hour.

  • EtOH Fully Automated Ethanol Extraction System

    EtOH Fully Automated Ethanol Extraction System

    A scalable 20-1000L ethanol platform that washes botanicals with chilled food-grade ethanol and recovers the solvent in a closed loop for clean, full-spectrum extracts.

  • Gas Chromatography Analysis System

    Gas Chromatography Analysis System

    A compact benchtop GC-FID analyser with a built-in hydrogen generator and dual columns for fast, low-cost potency, aroma-profile and residual-solvent testing.

  • Mold & Yeast Remediation System

    Mold & Yeast Remediation System

    A low-pressure decontamination system that removes mold, yeast and microbial load from botanical material and extracts at room temperature, with no heat or irradiation.

  • SHW 120L Subcritical Hot Water Extraction System

    SHW 120L Subcritical Hot Water Extraction System

    A solvent-free 120L production system that extracts polar, water-soluble compounds with pressurised hot water, delivering both a concentrated extract and an aromatic water.

  • SHW 60L Subcritical Hot Water Extraction System

    SHW 60L Subcritical Hot Water Extraction System

    A solvent-free 60L system that extracts polar, water-soluble compounds with pressurised hot water, yielding both a concentrated extract and a fragrant aromatic water.