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Linden

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COMERG • Linden extraction

Linden Blossom

Tilia tomentosa Moench.

Capture the honeyed scent of lime blossom with COMERG equipment. Our cold, room-temperature, low-pressure process lifts the soft, sweet, lightly green linden note, the rose-honey phenylethyl alcohol and its esters, straight from the fresh flower, one of perfumery's most loved and most fleeting scents.

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25% phenylethyl alcohol

The flower

A scent that lasts two weeks a year

Linden, the lime blossom, fills whole streets with a honeyed, slightly green sweetness for a brief window each summer. The scent comes largely from phenylethyl alcohol and its benzoate ester, the rose-honey facet perfumers prize, lifted by a touch of citronellol. The flowers are wonderfully nectarous, which is why bees make the famous linden honey from them.

We work with fresh blossoms, picked in late spring and processed cold so that soft, fleeting note survives. This is the silver linden, Tilia tomentosa, and like all linden it gives very little to a still, which is part of what makes a true linden extract so prized.

Raw material

Botanical nameTilia tomentosa Moench.
FamilyMalvaceae
Plant partBlossoms
ConditionFresh, cut
OriginBulgaria
HarvestMay to June

The extract

What the process delivers

Run on COMERG equipment, fresh linden yields a rich, true-to-bloom floral extract, batch after batch. Because the extraction is cold and solvent-light, with no high heat, the soft honey-rose note carries straight through to the finished material. The figures below are typical of a standardised BLin-50.1 grade.

25%Phenylethyl alcohol
≥50%Volatile oil v/w
<25 °CExtraction temp
97%Compound recovery
~650 kgBlossoms per kg extract
<0.1 g/kgSolvent residue

The method

Cold extraction, in three steps

No heat, no leftover solvent. This is what lets a flower that gives almost nothing to a still yield its true scent inside a COMERG aerosol system.

1

Pressurised R134a flooding

Non-toxic liquefied R134a gas is introduced to the fresh linden blossoms 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 phenylethyl alcohol, its esters, citronellol and the soft floral compounds, the delicate molecules that carry linden's honeyed note.

3

Recovery and pure extract

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

Aromatic profile

The compound fingerprint

Principal constituents identified by GC-MS, each above 1%. Phenylethyl alcohol leads, the rose-honey heart of the linden note, supported by its benzoate ester and citronellol, with natural plant waxes making up much of the rest.

Phenylethyl alcohol
25%
Nonadecane
11%
Heneicosane
9%
Tricosane
8%
Phytol
6%
Phenylethyl benzoate
6%
Citronellol
3%
0%10%18%25%+

The scent comes from phenylethyl alcohol, phenylethyl benzoate and citronellol; the nonadecane, heneicosane and tricosane are natural plant waxes carried through from the flower. Other extractables present. Per-batch GC-MS report available on request.

Specification

BLin-50.1 at a glance

Identity & origin

Botanical nameTilia tomentosa Moench.
Plant partBlossoms
OriginBulgaria
Product codeBLin-50.1
CAS No.94167-04-1
EINECS No.303-402-7

Production

MethodLiquefied-gas extraction
TemperatureBelow 25 °C
SolventFood-grade (Dir. 97/60/EC)
Solvent residue< 0.1 g/kg
StandardisationDeclared volatile oil
Concentration1 kg ≈ 600-700 kg blossoms

Physical

AppearanceYellow oily liquid
Volatile oil≥ 50% v/w (ASTA)
INCI nameTilia Tomentosa Flower Extract
DensityOn request
Refractive indexOn request
Flash pointOn request

Solubility & output

In oilsFully soluble
In 40% alcoholPartial
In waterInsoluble
UseEdible & fragrance
ContainerLined aluminium bottle
Shelf life2 years

Why linden, why cold

A fleeting floral, captured whole

A precious bloom

Tilia tomentosa, Bulgaria

Plant partFresh blossoms
Blossoms per kg extract~600-700 kg
Volatile oil≥ 50% v/w
HarvestMay to June, in bloom

Captured cold

Versus distillation, which gives little

Phenylethyl alcohol25% kept
Rose-honey noteCarried through
Process temperature< 25 °C
Soft floral facetsIntact

Applications

What you can make

Bakery & confectionery Honey & sweet products Beverages & teas Fine perfumery Skincare & cosmetics

This linden extract is edible and can be used concentrated or diluted in a carrier to suit the application. Typical filling rates for the concentrated extract in food are 0.3 to 5 mg per kilogram of product. Like all our extracts it is a raw material for formulation, not for direct or undiluted use.

Why the COMERG line

Built for the flowers others cannot capture

Linden is a perfect example. A flower that gives almost nothing to a still gives up its honeyed scent to a cold, gentle process. Our line is engineered around exactly that kind of fragile, high-value bloom.

Room temperatureR134a aerosol extraction works cold and at low pressure, so the soft, fleeting honey-rose note is never cooked off.
Captures the uncapturableWhere distillation yields almost nothing, cold gas extraction lifts a true, honeyed linden that smells like the living flower.
Fully automatedClosed-loop systems run the cycle for you, so results stay consistent and one operator can handle the line.
Gentle, fast cyclesLow-pressure extraction is quick and recovers up to 97% of what the flower will give, with no thermal damage.
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

For a delicate flower like linden the contrast is stark, distillation gives very little, while cold R134a extraction delivers a true, honeyed material.

FeatureCOMERG R134aSteam distillationSolvent (absolute)CO₂ supercritical
Process temperature< 25 °C (room temp)100-150 °C40-60 °C31-80 °C
Suits lindenYes, true noteNo, very low yieldPossible, harderPossible
Fragile moleculesPreservedLargely lostMostly keptMostly kept
Solvent residue< 0.1 g/kgNoneNeeds post-purgeNone
Energy use85% less vs solventHighMedium-highVery high
Special facilityNot requiredNot requiredRequiredHigh-pressure safety

From bloom to extract

The machines for linden

A complete COMERG line takes linden from fresh bloom 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 linden extract BLin-50.1.
Download PDF

Questions

Linden extraction, explained

A 100% natural linden flower extract from Tilia tomentosa, product code BLin-50.1. It reaches at least 50% volatile oil, led by around 25% phenylethyl alcohol, the rose-honey heart of the linden note, with no additives.

Linden flowers give very little oil, and roughly 1 kg of extract represents 600 to 700 kg of blossom. The scent is also famously fleeting, so a true, stable linden extract is rare and highly valued.

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

Roughly 1 kg of extract represents around 600 to 700 kg of fresh linden blossom, which is part of why the material is so precious.

Yes. Linden extract is edible, with typical filling rates of 0.3 to 5 mg per kilogram of product. It suits bakery, honey and sweet products and beverages, as well as perfumery and cosmetics, and is a raw material for formulation rather than for undiluted use.

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.

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 linden line

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

Equipment for processing linden

The machines below make up the linden line, the equipment that takes the bloom 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.

  • Stick & Seed Separation System

    Stick & Seed Separation System

    A sifting and air-separation line that sorts dried botanical biomass into three clean fractions – flower and leaf, stalk, and seed – ready for extraction or sale.