Cinnamon is a spice obtained from the inner bark of several species of trees in the genus Cinnamomum. Cinnamon is primarily used as an aromatic spice and flavoring additive in a wide variety of cuisines, sweet and savory dishes, breakfast cereals, snacks, teas, and traditional foods. The aroma and flavor of cinnamon come from its essential oil and its main component, cinnamaldehyde, as well as from several other components, including eugenol.
Cinnamon is the name for several species of trees and the commercial spice products that some of them produce. All are members of the genus Cinnamomum of the family Lauraceae. Only a few species of Cinnamomum are grown commercially for spices. Cinnamomum verum (AKA C. zeylanicum), known as "Ceylon cinnamon" after its origin in Sri Lanka (formerly Ceylon), is considered "true cinnamon", but most cinnamon in international trade comes from four other species, usually and more correctly referred to as "cassia": C. burmannii (Indonesian cinnamon or Padang cassia), C. cassia (Chinese cinnamon or Chinese cassia), C. loureiroi (Saigon cinnamon or Vietnamese cassia), and the less common C. citriodorum (Malabar cinnamon).

Etymology
The English word "cinnamon" comes from the Ancient Greek kinnámōmon (kinnámōmon, later κίνναμον: kínnamon), via Latin and Medieval French intermediate forms. The Greek was borrowed from a Phoenician word, which was similar to the related Hebrew word קנמון (qinnāmōn).
The name "cassia", first recorded in late Old English from Latin, ultimately derives from the Hebrew word קציעה qetsīʿāh, a form of the verb קצע qātsaʿ, "to strip the bark".
Early Modern English also used the names canel and canella, similar to the current names for cinnamon in many other European languages, which come from the Latin word cannella, a diminutive of canna, "tube", from the way the bark is rolled and dried.

Cinnamomum verum, which translates from Latin as "true cinnamon", is native to India, Sri Lanka, Bangladesh and Myanmar. Cinnamomum cassia is native to China. Related species, harvested and sold in modern times as cinnamon, are native to Vietnam ("Saigon cinnamon"), Indonesia and other countries in Southeast Asia with warm climates.

Cultivation

Cinnamon flowers:
Cinnamon is an evergreen tree characterized by oval-shaped leaves, thick bark, and berry-like fruit. When harvesting the spice, the bark and leaves are the main parts of the plant used. Cinnamon is cultivated by growing the tree for two years, and then by cutting the tree, that is, cutting the stems at ground level.
The stems should be processed immediately after harvest while the inner bark is still wet. The cut stems are processed by scraping off the outer bark and then hitting the branch evenly with a hammer to loosen the inner bark, which is then rolled into long rolls. Only 0.5 mm of the inner bark is used; the outer, woody part is discarded, leaving one-meter-long strips of cinnamon that are rolled into rolls. during drying. The treated bark dries completely in four to six hours, provided it is in a well-ventilated and relatively warm environment.

Cassia imparts a strong, spicy flavor and is often used in baking, especially in combination with cinnamon rolls, as it handles baking conditions well.Among cassia, Chinese cinnamon is generally medium to light reddish-brown in color, as all layers of the bark are used. Ceylon cinnamon, using only the thin inner bark, is lighter brown in color and has a thinner, less dense, and more crumbly texture. It is milder and more aromatic in flavor than cassia and loses much of its flavor when cooked.
Ceylon cinnamon sticks (buns) have many thin layers and can be easily ground into powder using a coffee or spice grinder, while cassia sticks are much harder.

Culinary use

Cinnamon bark is used as a spice, seasoning, and flavoring. It is used in the manufacture of chocolate, especially in Mexico. Cinnamon is often used in savory dishes with chicken and lamb. In the United States and Europe, cinnamon and sugar are often used to flavor cereals, bread-based dishes such as toast, and fruits, especially apples. It is also used in Portuguese and Turkish cuisine for sweet and savory dishes. Cinnamon can also be used in pickles and Christmas drinks such as avgolemono. Cinnamon powder has long been an important spice for enhancing the flavor of Persian cuisine, used in a variety of thick soups, drinks, and desserts.

Taste and aroma
The flavor of cinnamon is due to an aromatic essential oil that makes up 0.5 to 1% of its composition. This essential oil can be prepared by roughly pounding the bark, soaking it in seawater, and then rapidly distilling the whole. It is golden yellow in color, with a characteristic cinnamon odor and a very hot aromatic flavor. The spicy flavor and aroma come from cinnamaldehyde (about 90% of the essential oil from the bark) and, by reacting with oxygen as it ages, darkens in color and forms resinous compounds.
Cinnamon's constituents include about 80 aromatic compounds, including eugenol, which is found in the oil from the leaves or bark of cinnamon trees.

Alcoholic perfume
Cinnamon is used as a flavoring in cinnamon liqueurs, such as cinnamon-flavored whiskey in the United States and rakomelo, a cinnamon brandy popular in parts of Greece.

Medical research
Cinnamon has a long history of use in traditional medicine as a digestive aid, however, modern studies are unable to find evidence of any significant medicinal or therapeutic effects.
The Cochrane authors concluded: "There is insufficient evidence to support the use of cinnamon for type 1 or type 2 diabetes mellitus." The results in humans do not support the use of cinnamon for any health condition." However, the results of the studies are difficult to interpret because it is often unclear which type of cinnamon and which part of the plant was used.

A meta-analysis of trials of cinnamon supplements with lipid measurements reported lower total cholesterol and triglycerides, but no significant changes in LDL-cholesterol or HDL-cholesterol. Another reported no changes in body weight or insulin resistance.

Toxicity
More information: Coumarin
A systematic review of adverse events resulting from cinnamon use reported gastrointestinal upset and allergic reactions as the most commonly reported adverse events.

In 2008, the European Food Safety Authority reviewed the toxicity of coumarin, a component of cinnamon, and confirmed a maximum recommended tolerable daily intake (TDI) of 0.1 mg of coumarin per kilogram of body weight.Coumarin is known to cause liver and kidney damage at high concentrations and metabolic effects in humans with a CYP2A6 polymorphism. Based on this assessment, the European Union set a guideline for maximum coumarin content in foods of 50 mg per kilogram of dough in seasonal foods and 15 mg per kilogram in everyday baked foods.

The maximum recommended TDI of 0.1 mg coumarin per kg body weight is equivalent to 5 mg coumarin (or 5.6 g C. verum with 0.9 mg coumarin per gram) for a body weight of 50 kg. C as shown in the table below:

Due to the variable amount of coumarin in C. cassia, usually well above 1.0 mg coumarin per gram of cinnamon and sometimes up to 12 times, C. cassia has a low upper safe intake limit to meet the above TDI. In contrast, C. verum has only trace amounts of coumarin.