cinnamaldehyde

Herodotus reported that cinnamon sticks were gathered from cliffside nests built by birds too large to approach, baited down with chunks of dead ox: a good story sold by middlemen who did not want anyone finding the real source. What actually travels is a molecule, cinnamaldehyde, C₉H₈O, and it is not proof of anything by itself. A widely repeated finding that Phoenician flasks carried cinnamon from Southeast Asia in the Iron Age rests on detecting cinnamaldehyde in flask residue, and a 2017 review took the claim apart on exactly that ground: myrrh contains cinnamaldehyde too, so one compound cannot identify a particular plant. In this library it comes from cinnamon alone, seasoning six recipes across three kitchens: three spice blends, two savory dishes, and a smoothie.

Cinnamaldehyde dominates the bark oil of both commercial cinnamons, measured at 77.93 percent of the oil in one analysis, and is effectively what cinnamon tastes of either way. The two species diverge somewhere else. True cinnamon, from Sri Lanka, also carries eugenol and benzyl benzoate and essentially no coumarin; cassia carries little eugenol and a great deal of coumarin, anywhere from 700 to 12,200 milligrams per kilogram against true cinnamon's undetectable-to-190. That is a coumarin story, not a cinnamaldehyde one: the aldehyde that gives cinnamon its warmth is not the compound that makes cassia the one worth watching.

Cinnamaldehyde is named, in passing, as one of the compounds that activate TRPA1, the irritant receptor mustard oil and olive oil's oleocanthal also switch on, though the record does not give cinnamaldehyde its own numbers there. The documented caution in this bark belongs to coumarin instead: hepatotoxic in a small susceptible minority, capped by the European Food Safety Authority at a tolerable daily intake of 0.1 milligrams per kilogram of body weight, a limit ordinary cassia reaches at just under a level teaspoon for a sixty-kilogram adult. Cinnamaldehyde and coumarin travel together in the same bark but are not the same story, and clinical trials testing cinnamon against blood sugar have mostly failed to move the marker that matters, HbA1c, even when a fasting-glucose number looked promising. In this library it is cinnamaldehyde alone doing the work, the sweet-woody spine under six recipes across three kitchens, always traced to a stick or a spoonful of cinnamon.