Clove extract is bought on one number — the eugenol percentage — and that is exactly the problem. Eugenol is one of the cheapest phenolics in industrial commerce, available in quantity from clove stem oil, leaf oil and outright synthesis, so an extract can hit an impressive assay while containing far less genuine bud material than the buyer paid for. This guide covers how to specify grade, what a genuine Certificate of Analysis must show, and the origin question that separates a real clove bud extract from a eugenol carrier.
What Is Clove Extract?
Clove extract is a concentrated preparation made from the dried, unopened flower bud of Syzygium aromaticum, a Myrtaceae tree cultivated across Indonesia, Madagascar, Zanzibar, Sri Lanka and the hill tracts of southern India. The bud — the same article traded as the whole spice — is the part that matters. Clove stems and leaves also yield eugenol-rich oils, far more cheaply, and the difference between bud-derived and non-bud material is the central quality question in this category.
The defining constituent is eugenol, a volatile phenylpropene that dominates clove's essential-oil fraction, accompanied by eugenyl acetate and β-caryophyllene. Behind the volatiles sits a dense non-volatile polyphenol fraction — gallotannins, the ellagitannin eugeniin, and flavonoids — which is why whole clove ranks at or near the top of published ORAC tables among common spices. Treat that ranking as a compositional fact about the raw material, useful for polyphenol-positioned formulation, not as a promise about what a finished product will do.
How to Specify Grade: The Commercial Families
"Clove extract" spans several genuinely different materials, and the most common sourcing error is not stating which one you want:
- Nutraceutical grade — assayed to eugenol 60–70% by GC, the mainstream commercial grade for supplements, oral-care and food formats.
- Dental-pharma grade — eugenol 70–80% with tighter assay control, supplied as an ingredient input for dental materials and higher-specification oral-care applications.
- Water-soluble grade — for mouthwashes, rinses, beverages and clear formats where a partially soluble powder would sediment.
- Organic grade — certified-organic supply for certified product lines, with the certification chain documented.
Adjacent materials are different products entirely: clove oleoresin is a viscous flavour-industry material declared on volatile-oil content, and clove bud oil is a distilled essential oil. A supplier quoting "clove extract, $X/kg" without naming the grade family is quoting nothing.
Buyer tip: the eugenol percentage alone cannot tell you the extract was made from buds. Stem- and leaf-derived eugenol hits the same number at a fraction of the cost. Insist that eugenyl acetate is reported alongside eugenol on the CoA — it is abundant in bud material and nearly absent from the cheap sources. The chemistry is unpacked in our guide to eugenol and how clove extract is standardised.
The Question Most Buyers Never Ask
Ask your supplier: what is the eugenyl acetate content of this batch?
A genuine bud extract carries eugenyl acetate in meaningful proportion to its eugenol, together with a characteristic β-caryophyllene presence. An extract standardised up with stem-oil, leaf-oil or synthetic eugenol shows a strong eugenol peak sitting on an acetate reading close to zero — a profile no honest bud extraction produces. The question costs a supplier running a real GC method nothing to answer, and a refusal, or a puzzled silence, is itself the answer.
What a Genuine Clove Extract CoA Must Show
These are the specification limits SV Botanica supplies a standardised clove bud extract against. A complete, trustworthy CoA should carry every line below.
| Parameter | Specification / Limit | Method |
|---|---|---|
| Identification | Corresponds to eugenol — positive | By TLC |
| Eugenol (standardised grade) | 60–70% w/w (dry basis) | By GC |
| Eugenyl acetate / β-caryophyllene | Reported per batch | By GC |
| Loss on drying (105°C) | NMT 5.0% | IP-2014 |
| Total ash / acid-insoluble ash | NMT 8% / NMT 2% | IP-2014 |
| Particle size (#40 mesh) | NLT 95% w/w | Sieve |
| Residual solvent (ethanol) | NMT 5,000 ppm | By GC |
| Lead / Arsenic / Cadmium / Mercury | NMT 1.0 / 1.0 / 0.3 / 0.1 ppm | ICP-MS |
| Aflatoxins B1 / total | NMT 2 / NMT 4 ppb | HPLC-FLD |
| Pesticide residues | Complies (EU MRL, on request) | GC-MS / LC-MS/MS |
| Ethylene oxide | Not treated — declaration provided | LC-MS/MS (on request) |
| Microbiology (TPC / Y&M / pathogens) | NMT 1,000 / NMT 100 / negative | USP <2021>/<2022> |
| Shelf life | 24–36 months from manufacture | — |
Three lines deserve particular attention on clove specifically. The GC method column — eugenol is volatile, GC is the pharmacopoeial approach for clove materials, and "eugenol by UV" is an invitation to spiking. Acid-insoluble ash catches mineral bulking in a dark powder where colour hides a lot. And ethylene oxide matters because dried spice-derived materials are a recognised ETO risk category in the EU, where a positive finding means destruction of the consignment, not a discount.
Why Source Clove Extract from India?
Clove is grown in the Kerala and Tamil Nadu hills, and India additionally imports substantial bud volume for its enormous domestic spice trade — which means Indian extractors sit close to deep, liquid raw-material supply across origins. More importantly for a buyer, India has the densest concentration of standardised botanical-extract manufacturing anywhere, with GC assay, NABL-accredited laboratories and documentation practice built for regulated EU and US markets. Sourcing from a supplier who controls the specification and holds the CoA relationship, rather than a broker reselling an unseen lot, is the practical difference between a repeatable material and a lottery.
What to Ask Your Supplier
When evaluating clove extract suppliers for commercial supply, request the following as a minimum:
- Batch-specific CoA stating the eugenol percentage and the method — GC
- Eugenyl acetate and β-caryophyllene reported, not just the eugenol total
- TLC identity confirming correspondence with reference eugenol
- Bud-only, correct-species (Syzygium aromaticum) declaration and country of origin
- Heavy-metal report by ICP-MS with numeric limits for Pb, As, Cd, Hg
- Aflatoxin report and acid-insoluble ash figure
- Pesticide residue report against EU MRL, and a non-ETO declaration
- Residual solvent, solubility, mesh and full microbiological panel
- Declarations: non-irradiated, GMO-free, allergen status
Our companion clove extract supplier evaluation guide turns this into a scored checklist. SV Botanica supplies nutraceutical, dental-pharma, water-soluble and organic clove bud extract from certified manufacturing facilities in India, with full documentation available before any bulk commitment and samples for qualified buyers.
Source Standardised Clove Extract from India
Eugenol 60–70% by GC · 70–80% dental-pharma, water-soluble & organic grades · CoA-backed · samples for qualified buyers