Candy, cider, chocolate, cakes, cookies... cinnamon is all around this time of year. Or is it cassia?
Cinnamomum zeylanicum ("true" cinnamon) and Cinnamomum cassia ("fake" cinnamon) are two members of the large Cinnamomum tree species1. The trees' inner bark is used to produce quills (curly sticks) and spice (powder).
The casual observer might not be able to spot the difference between cinnamon and cassia quills or powder. One difference would become crystal clear at the cash register.
Ten pounds of cinnamon sticks or powder will set you back about $140, while 10 lbs of cassia is a steal at just $50. Cinnamon oil, produced via steam distillation of the tree's inner bark, runs about $40 for roughly 1 teaspoon (5 mL). The same volume of cassia oil, made by distilling a 'mixed bag' of leaves, twigs and bark, is a bargain at just $7.
That's a big price difference for plant products that both owe much of their taste and aroma to one chemical popularly known as 'cinnamaldehyde'.
Cinnamaldehyde, a yellowish liquid at room temperature, accounts for ≈75% of cinnamon oil’s volume and ≈80-90% of cassia oil’s volume. Though cinnamaldehyde is the dominant scent chemical in Cinnamomum barks, other chemicals contribute to their aromas If you've ever thought cinnamon (or cassia) smelled a bit similar to cloves, that's because Cinnamomum barks contain eugenol, the chemical responsible for cloves' aroma. Also a yellowish liquid at room temperature, eugenol accounts for about 2.5% of cinnamon oil's volume and 1% cassia oil's volume. Though the different levels of cinnamaldehyde and eugenol may be enough for chemists to distinguish cinnamon from cassia, looking out for one other chemical can confirm the call. That chemical is coumarin, a oil-soluble white solid noted for smelling and tasting like vanilla2. Trace quantities of coumarin are found in cinnamon bark (≈.019% by mass), but cassia bark contains a much high concentration (≈1.2% by mass). Cinnamaldehyde, eugenol, coumarin - these are just three of the hundreds of chemicals found in C. zeylanicum and C. cassia barks. Chemists and side-by-side tast testers can distinguish between cinnamon and cassia because many of these chemicals are present in different enough amounts.
Tasters often note that cinnamon has a sweeter, subtler taste and scent than cassia - unless those tasters are Americans.
The FDA allows many Cinnamomum varieties to be marketed as cinnamon – whether they’re “true” cinnamon or not. This generous classification scheme, along with the cheap price of C. cassia, means there's nearly a zero chance you're sprinkling C. zeylanicum in your morning latte. The absence of cinnamon from the American kitchen (or cafe) was catalogued by researchers in the mid-nineties (Jayatilaka, Poole, Poole, and Chichila; 1995). Comparing 41 cinnamon and cassia samples from seven countries to cinnamon and cassia standards, researchers found that American brands - such as McCormick and Spice Island - were not cinnamon. By and large, we Americans4 are importing and enjoying cassia - the "poor man's cinnamon". Or as we call it in America, 'cinnamon'.
Other countries aren't so fast-and-loose with their Cinnamomum classification guidelines. Some countries have stricter labeling guideline simply because of the vast differences in Cinnamomum products' values and the real fear of fraud. Nobody paying top dollar for C. zeylanicum would be pleased to find they're vastly overpaid for C. cassia. Another reason for stricter labeling or government issued advisories is the chemical coumarin.
Like all chemicals, the amount consumed determines whether it's harmless or harmful. Too much coumarin has been found to cause liver damage in laboratory animals. Though this damage is not permanent, coumarin consumption should be limited. The FDA, and many equivalent agencies around the globe, banned coumarin as a food additive decades ago. Of course, coumarin isn't added to cassia - it's there naturally. The average person's consumption of "fake" cinnamon typically puts them in the 'safe zone' of coumarin consumption. Sometimes, however, government agencies have to caution citizens on their cassia consumption.
Back in 2006, Germany's Federal Institute for Risk Assessment (BfR), drew attention to "typical German Christmas cookies" that are typically packed with cinnamon. Turned out, that cinnamon was actually cassia and those cookies had coumarin levels which prompted the BfR to advise citizens aim for "moderate consumption" of these treats. If heavy consumption of "fake" cinnamon is more your style, here is what the BfR says about coumarin...
From the use of coumarin in the medicinal field, it is common knowledge that relatively low doses can already cause liver damage in a small group of particularly sensitive individuals if the medicinal products are administered over a few weeks. In minor cases this leads to an elevation of liver enzymes in blood, in severe cases to inflammation of the liver which manifests as jaundice. The exact mechanism of action is not known but the effects are reversible.
Consumers who have eaten large amounts of cinnamon in the past have no reason to worry that their liver has suffered permanent damage. The liver of patients who developed minor to moderate liver inflammation caused by the administration of coumarin recovered fully just a few weeks after [it] was discontinued.
Coumarin concerns prompted the FDA to call-out fraudulent vanilla extract in 2009. Coumarin, with its vanilla-like aroma and taste2, is used to produce bargain priced "vanilla extract". Real vanilla doesn't contain coumarin and, like "true" cinnamon, is pricey. The FDA advised consumers to skip the too-cheap-too-be-real vanilla.
Speaking of cheap fakes, the FDA hasn't issued a coumarin-related cassia caution3. I take this to mean I can continue my (fake) cinnamon habit.
1There are over 250 Cinnamomum tree varieties, including Cinnamomum Camphor. This post focuses on the two major varieties. Besides C. zeylanicum (also known as ‘Ceylon cinnamon’) and C. cassia, Cinnamomum loureirii and Cinnamomum burmanii are also routinely traded as 'cinnamon' in the US and abroad. The concentration of chemical constituents can vary significantly among varieties.
2Coumarin is also noted as having a sweet grass scent. As a vanilla mimic, coumarin has a distinctly bitter aftertaste which sugar may be used to disguise.
3No such warning was found during a 'cassia' or 'cinnamon' searches of the FDA's 'Consumer Updates'. Please alert me to such an advisory in the comments.
4Americans aren't alone in our love of a fake. Researchers found that cinnamon purchased in Canada, Germany, Korea, and Syria was actually cassia. The British, however, are enjoying the real thing.
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Bundesinstitut für Risikobewertung. “Frequently Asked Questions about coumarin in cinnamon and other foods”. FAQs. BfR, 30 October 2006
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US Food and Drug Administration. "CPG Sec. 525.750 Spices - Definitions". Inspections, Compliance, Enforcement, and Criminal Investigations. FDA, 18 September 2009.
US Food and Drug Administration. "Some "Vanilla Extract" Produced in Mexico is No Bargain". Consumer Updates. FDA, 26 March 2009.
Woehrlin, F., Hildburg, F., Abraham, K., and Preiss-Weigert, P. (2010) Quantification of Flavoring Constituents in Cinnamon: High Variation of Coumarin in Cassia Bark from the German Retail Market and in Authentic Samples from Indonesia. J. Agric. Food Chem., 58(19), p10568–10575
Apple butter cocktail image source
Chemical images from their ChemSpider entries (see References)
Cinnamon (cassia?) sticks image is clip art from Word