How to Buy L-Menthol: Grade, Isomer and Specification
L-Menthol (Menthol Crystal, CAS 2216-51-5) is a flavour, fragrance and sensory ingredient, and buying it well means fixing the isomer, the specification and the packing up front. This page sets out what to confirm before you request a quotation.
1. Confirm the isomer (most important)
Menthol exists as several stereoisomers; only the L-(-)-isomer has the full natural mint character and cooling intensity. Other grades (D-, racemic) are cheaper but weaker.
| Grade | CAS | Optical rotation | Note |
|---|---|---|---|
| L-(-)-Menthol (crystal) | 2216-51-5 | About -45° to -51° | Natural isomer; strongest cooling |
| DL- (racemic) menthol | 89-78-1 | About 0° | Cheaper; weaker cooling |
| D-(+)-Menthol | 15356-60-2 | About +50° | Mirror image |
2. Fix the specification
| Parameter | Specification |
|---|---|
| Appearance | Colourless crystals |
| Odour | Minty, cool |
| Melting point | 41 – 44 °C |
| Optical rotation (25 °C) | -45° to -51° |
| Non-volatile matter | 0.05% max |
| Residue on ignition | 0.1% max |
| Heavy metals | 10 ppm max |
| Arsenic (As) | 3 ppm max |
| Purity | 99% min |
3. Choose the form
| Form | When to choose it |
|---|---|
| Crystal | Standard; where the natural L-isomer is wanted |
| Powder / flakes | Faster dissolution/blending in some processes |
4. Packaging and storage
- Packing – 25 kg net fibre drums (as specified).
- Storage – sealed, cool and dry, away from heat and strong odours; menthol is volatile and sublimes if left open.
- Documents – per-batch COA and SDS.
5. Seasonality and price planning
Menthol is unusual: a large part of supply starts as the mint crop, so price is seasonal – tightest between crops and easier after a good harvest. Plan purchases around the harvest cycle and confirm the isomer/specification precisely, because the optical rotation is a real cost driver.
6. A short enquiry checklist
- Product and CAS 2216-51-5; grade (L- vs DL-/racemic).
- Specification (optical rotation, melting point, purity).
- Form (crystal vs powder/flake).
- Packing (25 kg fibre drums) and delivery port.
- Tonnage and Incoterm (FOB / CIF).
- Documents (COA, SDS).
Frequently Asked Questions
What should I check first when buying menthol?
The isomer – confirm L-(-)-menthol by its optical rotation (-45° to -51°).
Is racemic menthol a substitute?
Only where the weaker cooling and different odour are acceptable; it is cheaper but not equivalent.
How is menthol packed?
25 kg net fibre drums.
Is menthol seasonal?
Yes – natural supply follows the mint harvest, so price is seasonal.
Do you provide a COA per batch?
Yes – a certificate of analysis for each batch, plus an SDS.
Related reading
- L-Menthol (CAS 2216-51-5): properties, production and applications
- L-Menthol vs peppermint oil and synthetic coolants
- L-Menthol in oral care and formulation
- L-Menthol (Menthol Crystal, CAS 2216-51-5) – product page
PolyBlueChem supplies L-Menthol (Menthol Crystal, CAS 2216-51-5) to specification in 25 kg fibre drums, with per-batch COA and SDS and FOB/CIF delivery. Contact us with your grade, tonnage and delivery port.