Overview
ISO 3033-3:2005 specifies quality criteria for oil of spearmint - Indian type (Mentha spicata L.), redistilled oil. The standard defines physical, sensory and compositional requirements and prescribes analytical approaches to facilitate consistent quality assessment and trade of this essential oil variety.
Key topics and requirements
- Scope: Applies to steam-distilled then redistilled spearmint oil yielding a minimum carvone content of 60%.
- Appearance & colour: Clear mobile liquid, colourless to pale yellow.
- Odour: Characteristic carvone aroma with an herbaceous note.
- Physical constants:
- Relative density (20 °C): 0.9210 – 0.9380
- Refractive index (20 °C): 1.4840 – 1.4910
- Optical rotation (20 °C): −59° to −48°
- Miscibility: Must be miscible in 70% ethanol such that no more than 3 volumes of ethanol are needed to obtain a clear solution with 1 volume of oil.
- Carbonyl value: Minimum 224, corresponding to 60% carvone (expressed as carvone).
- Chromatographic profile (normative): Gas chromatography is required. Representative components and typical ranges include:
- Carvone: 60.0–70.0%
- Limonene: ~11.5–16.5%
- 3‑Octanol: 0.6–1.4%
- trans‑Sabinene hydrate: 0.5–1.0%
- cis‑Dihydrocarvone: 1.0–2.5%
- trans/cis‑dihydrocarvyl acetates, cis‑jasmone, β‑bourbonene: minor components within specified small ranges
- Viridiflorol: not detectable
- Analytical & test methods: References and methods include GC profiling (ISO 11024-1/2), density (ISO 279), refractive index (ISO 280), optical rotation (ISO 592), carbonyl value (ISO 1271), miscibility (ISO 875).
- Flashpoint (informative): Mean value reported as +58 °C (Setaflash).
Applications and users
ISO 3033-3:2005 is used by:
- Essential oil producers and distillers to demonstrate product conformity and optimize redistillation targeting carvone content.
- Quality control laboratories for specification testing (GC, density, refractive index, optical rotation).
- Flavor & fragrance manufacturers and ingredient buyers who require consistent organoleptic and compositional properties.
- Regulatory, transport and safety professionals for labelling, packaging and hazard information (flashpoint guidance).
- Traders and exporters/importers for contract specification and dispute resolution.
Related standards
- ISO 3033 series: Part 1 (native type), Part 2 (Chinese type), Part 4 (Scotch variety)
- Supporting ISO references: ISO 212, 279, 280, 592, 875, 1271, ISO 11024-1/2, ISO/TR 210, ISO/TR 11018
Keywords: ISO 3033-3:2005, oil of spearmint Indian type, Mentha spicata, carvone, essential oils standard, gas chromatography, flashpoint, quality assessment.