Calamus absolute

Damp root, warm spice, a hint of cinnamon. Earthy, woody and lightly leathery. A sweet, slightly powdery base.

The 51st Amendment of the IFRA Standards has a standard on cis- and trans-asarone (β-asarone and α-asarone). Both are prohibited as fragrance ingredients. Oils or extracts containing asarone, such as calamus, may only be used so that total asarone in the finished product does not exceed 0.01 percent.

In the United States, calamus and its derivatives are prohibited in food under 21 CFR 189.110.

β-Asarone content depends strongly on the plant's ploidy: the North American diploid has almost none, the Indian tetraploid a high level. An asarone analysis of the lot is essential to calculate limits. Store dark, sealed and cool.

Acorus calamus is a herb of marshes and water margins, widespread in Asia, Europe and North America. The library calls Acorus calamus thạch xương bồ; some Vietnamese sources use that name for the related Acorus gramineus and call A. calamus thủy xương bồ. The aromatic part is the rhizome.

The species has several ploidy types. The diploid (var. americanus) of North America, the triploid of Europe and the tetraploid of India and East Asia differ clearly in composition. The most important difference is β-asarone content, from near zero to very high. The library has separate pages for the three oil types.

The absolute is made from dried rhizome by solvent extraction, then processed with ethanol. Compared with the oil, it keeps more heavy matter and smells sweeter and more powdery.

β-Asarone has been shown to cause cancer in rodents in toxicity studies. IFRA therefore prohibits asarone as an ingredient and limits total asarone in products from natural sources. In the United States, calamus has been banned from food since 1968.

In perfumery, calamus was once a spicy root note in chypres and leather accords. Today its use depends on low-asarone sources and full analytical data.