Spearmint oil
Under the IFRA Standards a rinse-off soap may hold up to 0.27 % of this oil, a limit set by its Carvone.
IFRA maximum for soap
Restricted constituents, at the typical levels IFRA's annex gives:
- l-Carvone
- 66.07 %
- 1-Octen-3-yl acetate
- 0.06 %
- Hexen-2-al
- 0.02 %
Worked out from typical levels. A supplier's certificate for your lot comes first, and its figure is the one to follow.
Check a blend against its IFRA limits and list its allergens in the fragrance and allergen calculator.
How essential oils behave in soap, and how much to use: Scenting soap.
Identity and labelling
Mentha Viridis Leaf Oil
- Botanical name
- Mentha spicata
- CAS
- 84696-51-5, 8008-79-5
- EC
- 283-656-2
The EU names this oil itself as a fragrance allergen (Regulation (EU) 2023/1545, Annex III entry 362): it goes on the label by name above 0.01 % in a rinse-off product.
What it is and how it behaves in soap
Spearmint oil is steam-distilled from the fresh flowering tops of Mentha spicata (ISO 3033), and in the United States most of it comes from Washington State (USDA). It is mostly carvone and smells sweet and green, the mint of chewing gum; Fisher finds it gentler and sweeter than peppermint.
Faiola's 2013 book lists spearmint among the oils that behave well in cold process, and her later recipe uses it at 2.1 % of the oils. Carvone holds the IFRA figure on this page to a small fraction of that, and the figure is the ceiling. In practice a little spearmint can soften peppermint or lift a blend, but it cannot carry a bar on its own.
For a strong mint bar, peppermint is the oil to use.
Recipes that use it
Sources
- CosIng, the cosmetic ingredient database: MENTHA VIRIDIS LEAF OIL, European Commission
- Commission Regulation (EU) 2023/1545 amending Regulation (EC) No 1223/2009 as regards labelling of fragrance allergens in cosmetic products, European Commission. Annex, entry 362
- ISO 3033-1:2005, Oil of spearmint, Part 1: Native type (Mentha spicata L.), International Organization for Standardization (2005). Steam distillation of the fresh above-ground parts of the flowering plant
- Crop production, Northwest region, 2024 (press release), USDA National Agricultural Statistics Service (2025). Spearmint oil production, most of it in Washington
- David Fisher, The Complete Photo Guide to Soap Making, Creative Publishing International (2018). Spearmint is gentler and sweeter than peppermint; use mints sparingly
- Anne-Marie Faiola, Soap Crafting, Storey Publishing (2013). Spearmint among the essential oils that are typically wonderful in cold process soap
- Anne-Marie Faiola, Pure Soapmaking, Storey Publishing (2016). Spearmint with patchouli at 2.1 % of the oils