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CLOVE

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COMERG • Clove extraction

Whole Clove

Syzygium aromaticum

Turn clove buds into a powerful, food-grade extract with COMERG equipment. Our cold, room-temperature, low-pressure process captures the deep, warm sweetness of the bud, the eugenol that defines clove and gives it one of the strongest natural antioxidant profiles of any spice.

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70% eugenol

The spice

The dried flower bud

Clove is the unopened flower bud of the tropical evergreen Syzygium aromaticum, picked and dried before it can bloom. Its warm, sweet, slightly numbing aroma comes overwhelmingly from eugenol, the compound that has made clove a fixture of spice racks, perfumery and traditional dental preparations for centuries.

The buds are milled and processed cold, so the finished extract carries the full depth of the spice. Nothing is added, and the natural balance of eugenol and its supporting compounds is preserved.

Raw material

Botanical nameSyzygium aromaticum
FamilyMyrtaceae
Plant partBud
ConditionDried, ground
OriginIndia
AvailabilityAll year

The extract

What the process delivers

Run on COMERG equipment, clove buds yield a standardised, high-strength extract, batch after batch. Because the extraction is cold and solvent-light, with no high heat, the deep warm character carries straight through to the finished oil. The figures below are typical of a standardised BClo-90.1 grade.

≥90%Volatile oil v/w
70%Eugenol
0.011DPPH IC50 mg/ml
<25 °CExtraction temp
97%Compound recovery
~10 kgBuds 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 extract keeps the full clove character.

1

Pressurised R134a flooding

Non-toxic liquefied R134a gas is introduced to the milled clove buds 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 eugenol, eugenyl acetate and caryophyllene, while the heat-sensitive top notes stay structurally intact.

3

Recovery and pure extract

The R134a is fully recovered and recycled in a closed loop. What is left is a concentrated clove extract, at least 90% volatile oil, with under 0.1 g/kg residue.

Aromatic profile

The compound fingerprint

Principal constituents identified by GC-MS, each above 1%. Eugenol dominates the profile, backed by eugenyl acetate and caryophyllene, which together give clove its deep, warm, faintly sweet signature.

Eugenol
70%
Eugenyl acetate
13%
beta-Caryophyllene
10%
α-Humulene
1%
Caryophyllene oxide
1%
0%30%50%70%+

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

Specification

BClo-90.1 at a glance

Identity & origin

Botanical nameSyzygium aromaticum
Plant partBud
OriginIndia
Product codeBClo-90.1
CAS No.84961-50-2
EINECS No.284-638-7

Production

MethodLiquefied-gas extraction
TemperatureBelow 25 °C
SolventFood-grade (Dir. 97/60/EC)
Solvent residue< 0.1 g/kg
StandardisationDeclared volatile oil
Concentration1 kg ≈ 8-12 kg buds

Physical

AppearanceYellow clear oily liquid
Volatile oil≥ 90% v/w (ASTA)
INCI nameEugenia Caryophyllus Extract
Density1060 g/l
Refractive index1.5264
Acid value43.1 mg KOH/g

Solubility & output

In oilsFully soluble
In 40% alcoholPartial
In waterInsoluble
Flash point> 61 °C
ContainerLined aluminium bottle
Shelf life2 years

Why clove, why cold

A powerful bud, captured whole

A concentrated bud

Syzygium aromaticum, India

Plant partBuds, milled
Buds per kg extract~8-12 kg
Volatile oil≥ 90% v/w
AntioxidantDPPH IC50 0.011 mg/ml

Captured cold

Versus steam distillation

Eugenol70% retained
Eugenyl acetate13%
Process temperature< 25 °C
Top notesPreserved

Applications

What you can make

Food & flavour Bakery & confectionery Fine perfumery Oral & dental care Natural antioxidant Candles & home fragrance

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 20 to 200 mg per kilogram of product.

Why the COMERG line

Built for potent spice like clove

The strength and antioxidant power above are not an accident of the bud alone, they are what the right equipment makes repeatable. Our line is engineered around the things that matter when you process a high-value spice.

Room temperatureR134a aerosol extraction works cold and at low pressure, so the volatile top notes are never cooked off.
Keeps the eugenolEugenol carries almost the whole clove character and its antioxidant strength. Cold extraction concentrates it cleanly into the extract.
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 bud'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 more of the clove, with a clean, high-strength 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%
EugenolConcentratedRetained, some lossRetainedMostly retained
Solvent residue< 0.1 g/kgNoneNeeds post-purgeNone
Energy use85% less vs solventHighMedium-highVery high
Special facilityNot requiredNot requiredRequiredHigh-pressure safety

From bud to extract

The machines for clove

A complete COMERG line takes clove from raw bud 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 clove extract BClo-90.1.
Download PDF

Questions

Clove extraction, explained

A 100% natural clove bud extract, product code BClo-90.1. It reaches at least 90% volatile oil, led by around 70% eugenol, with no additives.

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.

Clove's character and its strong antioxidant activity both come from eugenol and a small set of supporting compounds. Cold R134a extraction concentrates them cleanly without prolonged heat altering the profile.

Roughly 1 kg of extract represents around 8 to 12 kg of dried, milled clove buds, a high yield that reflects how oil-rich the bud is.

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 clove line

Tell us your throughput and target product. We will recommend the right system, share a yield estimate for your clove buds, 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 clove line

Equipment for processing clove

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

  • 1000L HTE Fully Automated Aerosol Extraction System

    1000L HTE Fully Automated Aerosol Extraction System

    An industrial-scale aerosol extraction system for very high-volume, room-temperature, residue-free processing of any botanical.

  • 100L HTE Fully Automated Aerosol Extraction System

    100L HTE Fully Automated Aerosol Extraction System

    A commercial-scale low-pressure aerosol system that gently extracts essential oils and aromatics from any botanical at room temperature, with no residue.

  • 10L HTE Fully Automated Aerosol Extraction System

    10L HTE Fully Automated Aerosol Extraction System

    An entry-level, fully automated low-pressure aerosol system that gently extracts essential oils and aromatics from virtually any botanical at room temperature, with no residue.

  • 10T Conveyor Dryer System

    10T Conveyor Dryer System

    A continuous belt dryer that gently dries freshly harvested botanical biomass on a four-layer, 12 m mesh belt at an adjustable 0-90 °C, fed and discharged automatically.

  • 150L Fully Automated Compound Remediation System

    150L Fully Automated Compound Remediation System

    A production-scale system that refines large lots of botanical extract to a fixed specification at room temperature, with no thermal damage to the active profile.

  • 2000L HTE Fully Automated Aerosol Extraction System

    2000L HTE Fully Automated Aerosol Extraction System

    Our largest aerosol extraction platform, built for maximum-volume industrial production with the same gentle, residue-free low-pressure process.

  • 200L HTE Fully Automated Aerosol Extraction System

    200L HTE Fully Automated Aerosol Extraction System

    A high-capacity commercial low-pressure aerosol system for room-temperature, residue-free extraction of essential oils and aromatics from any botanical.

  • 20L Aerosol Extraction System

    20L Aerosol Extraction System

    A compact production-scale low-pressure aerosol system that gently extracts essential oils and aromatics from any botanical at room temperature, with no residue.

  • 20L MAX HTE Fully Automated Aerosol Extraction System

    20L MAX HTE Fully Automated Aerosol Extraction System

    A dual-vessel 20L MAX system that doubles throughput while keeping the same gentle, room-temperature, residue-free aerosol extraction for any botanical.

  • 25L Fully Automated Compound Remediation System

    25L Fully Automated Compound Remediation System

    A pilot-scale system that scales a validated remediation method to repeatable batches, stripping targeted impurities from extract while protecting the active profile.

  • 30L Ultrasonic Extraction System

    30L Ultrasonic Extraction System

    A 30L ultrasonic-assisted extraction system that uses 20 kHz cavitation to rupture plant cells and release oils into solvent quickly, at low temperature, with vacuum filtration.

  • 500L HTE Fully Automated Aerosol Extraction System

    500L HTE Fully Automated Aerosol Extraction System

    A large-scale industrial aerosol system delivering high-volume, room-temperature, residue-free botanical extraction at low pressure.

  • 500L Vacuum Drying Oven with Drawer

    500L Vacuum Drying Oven with Drawer

    A production-scale 18 cu ft vacuum oven with a pull-out drawer and integrated pump that purges and dries large batches of botanical extract at low temperature.

  • 50L Crystallization Reactor

    50L Crystallization Reactor

    A 50L jacketed reactor that crystallises high-purity botanical isolates from a distilled feed under precise temperature and agitation control, with repeated recrystallisation for maximum purity.

  • 50L HTE Fully Automated Aerosol Extraction System

    50L HTE Fully Automated Aerosol Extraction System

    A floor-standing production-scale low-pressure aerosol system that gently extracts essential oils and aromatics from any botanical at room temperature, with no residue.

  • 50L Vacuum Drying Oven

    50L Vacuum Drying Oven

    A compact 2 cu ft vacuum oven that purges residual solvent and gently dries botanical extracts at low temperature under vacuum, protecting colour, aroma and actives.