21 CFR § 189.110 - Calamus and its derivatives.
(a) Calamus is the dried rhizome of Acorus calamus L. It has been used as a flavoring compound, especially as the oil or extract.
(b) Food containing any added calamus, oil of calamus, or extract of calamus is deemed to be adulterated in violation of the act based upon an order published in the Federal Register of May 9, 1968 (33 FR 6967).
(c) The analytical method used for detecting oil of calamus (β-asarone) is in the “Journal of the Association of Official Analytical Chemists,” Volume 56, (Number 5), pages 1281 to 1283, September 1973, which is incorporated by reference. Copies are available from the AOAC INTERNATIONAL, 481 North Frederick Ave., suite 500, Gaithersburg, MD 20877, also from the Office of Food Additive Safety (HFS-200), Center for Food Safety and Applied Nutrition, Food and Drug Administration, 5001 Campus Dr., College Park, MD 20740, 240-402-1200, or available for inspection at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.