Cinnamon is derived from the inner bark of trees belonging to the genus Cinnamomum. The most commonly used types are Cinnamomum verum (true cinnamon or Ceylon cinnamon) and Cinnamomum cassia (cassia). Below, I'll describe the morphological and microscopical characters of cinnamon:



Morphological Characters

  1. Shape and Appearance:

    • The bark is usually available in the form of quills or pieces. Quills are formed by rolling thin pieces of bark into cylindrical shapes.
    • Ceylon cinnamon is light brown in color, thin, and forms multiple layers when rolled into a quill. It has a smoother surface with finer, more fragile layers.
    • Cassia cinnamon is thicker, dark brown or reddish-brown, and forms single-layered quills. The surface is rougher compared to Ceylon cinnamon.

  2. Texture:

    • Ceylon cinnamon is relatively fragile and can be easily broken by hand.
    • Cassia cinnamon is thicker and harder to break.

  3. Fragrance:

    • Both types of cinnamon have a characteristic aromatic odor due to the presence of essential oils, mainly cinnamaldehyde.
    • Ceylon cinnamon tends to have a sweeter and more delicate aroma, whereas cassia cinnamon is stronger and more pungent.

  4. Taste:

    • The taste is aromatic, sweet, and slightly pungent. Ceylon cinnamon is generally milder, while cassia is more intense and astringent.

Microscopical Characters

Under a microscope, the powdered form of cinnamon reveals several distinctive features:

  1. Cork Cells:

    • Cinnamon bark contains characteristic cork cells, which appear polygonal and thin-walled, forming the outer protective layer of the bark.

  2. Parenchyma:

    • Numerous parenchyma cells containing starch grains are visible. The starch grains are simple, oval, or polygonal.

  3. Sclereids:

    • Sclereids, or stone cells, are found abundantly in cinnamon. These are thick-walled, lignified cells with numerous pits, which contribute to the hardness of the bark.

  4. Fibers:

    • Cinnamon contains lignified fibers that are long and pointed. These fibers are visible throughout the bark and give it its strength.

  5. Calcium Oxalate Crystals:

    • Calcium oxalate crystals, often in the form of prismatic or cluster crystals, can be seen scattered throughout the parenchyma cells.

  6. Oil Cells:

    • Essential oil cells, containing cinnamaldehyde, are found distributed in the cortical region. These cells are filled with volatile oil that gives cinnamon its distinctive aroma.

  7. Medullary Rays:

    • Cinnamon bark contains medullary rays, which are the radially arranged parenchyma tissues that store nutrients.

Differences Between Cinnamomum verum and Cinnamomum cassia Microscopically

  • Cinnamomum verum tends to have finer and thinner sclereids, while Cinnamomum cassia has more robust sclereids.
  • The fibers in cassia are typically longer and thicker compared to those in Ceylon cinnamon.

These morphological and microscopical characteristics are important for the identification and quality control of cinnamon, particularly in differentiating between Cinnamomum verum and Cinnamomum cassia, which vary in quality and medicinal properties.