Coumarin is a phytochemical plant ingredient that gives fresh hay and dried woodruff, for example, its characteristic smell and is also found in various butterfly flowers, dates, tonka beans and various types of cinnamon. In addition to woodruff, cassia cinnamon contains, in contrast to Ceylon cinnamon, comparatively high amounts of coumarin (3 g/kg) 1,2.
Starting product for the coumarin synthesis in the plant is cinnamic acid. Coumarin is partially glycosidically linked in the plant and is only released when the cell structure is destroyed by enzymatic splitting of the sugar.
What are the risks associated with coumarin?
In animal experiments, hepatotoxic properties of coumarin have been determined. As a result, the use of coumarin as a flavouring agent has been restricted by law in the EU. In order to keep the risk of coumarin as low as possible, a tolerable daily intake (TDI) was derived by the Federal Institute for Risk Assessment (BfR). The amount that can be ingested daily for a lifetime is 0.1 mg coumarin per kg body weight. This value was confirmed by the European Food Safety Authority (EFSA) 3.
In general, the EU Flavour Regulation (Annex III Part A of Regulation (EC) No 1334/2008 ) does not allow the addition of the substance coumarin to foods as such. Since 2011, specific maximum levels apply throughout the EU for certain ready-to-eat compound foods that may naturally contain coumarin, in accordance with Annex III Part B of Regulation (EC) No 1334/2008. The maximum levels refer to the following compound foods: desserts: 5 mg/kg, fine bakery ware: 15 mg/kg (except for traditional and/or seasonal bakery ware where cinnamon is mentioned on the label; there: 50 mg/kg) and breakfast cereals including muesli: 20 mg/kg. Currently the coumarin content of cinnamon has not been subject to a maximum level.
The ifp Institut für Produktqualität offers a broad spectrum of contaminants and the analysis of various food ingredients with flavour properties such as coumarin. The quantitative determination of the substance is carried out using high-performance liquid chromatography (HPLC).