Essential Oil - Cassia
Essential Oil – Cassia
Botanical Information
Cassia (Cinnamomum cassia) belongs to the Lauraceae family and is also known as Chinese cinnamon, cassia cinnamon, false cinnamon, cassia lignea, Cinnamomum aromaticum, and Laurus cassia. It is a slender evergreen tree that can grow up to 20 metres tall, with leathery green leaves and clusters of small white flowers. For commercial cultivation, the trees are often regularly pruned to encourage bushy growth and make harvesting easier.
Habitat and Cultivation
Cassia is native to the southeastern regions of China and is also cultivated in Vietnam and parts of India, particularly the Cochin region. It thrives in warm, tropical climates with fertile, well-drained soils and has become an important commercial spice and essential oil crop throughout Asia.
Related Species
Cassia is closely related to Ceylon cinnamon (Cinnamomum verum), although the two should not be confused. Ceylon cinnamon is generally considered milder and safer, while cassia contains much higher concentrations of cinnamaldehyde. Several other regional varieties of Cinnamomum are also cultivated for essential oil production.
Traditional Uses
Cassia has been widely used for centuries as both a culinary spice and a traditional herbal remedy. Similar to Ceylon cinnamon, it has traditionally been used to relieve digestive complaints such as indigestion, flatulence, colic, diarrhoea, and nausea. It has also been employed in folk medicine to help manage the common cold, rheumatic discomfort, kidney disorders, and certain reproductive complaints. The powdered bark remains recognized in the British Herbal Pharmacopoeia as a traditional remedy for flatulent dyspepsia and colic accompanied by nausea.
Therapeutic Actions
Traditionally, Cassia essential oil has been regarded as antidiarrhoeal, antiemetic, antimicrobial, astringent, carminative, and antispasmodic. These properties explain its historical use in supporting digestive health and combating microbial infections.
Extraction Method
Cassia essential oil is produced in two forms. Leaf oil is obtained through steam distillation of the leaves, while bark oil is produced by water distillation of the bark, leaves, twigs, and stems.
Aroma and Characteristics
The leaf oil ranges from brownish-yellow to pale yellow after rectification and possesses a warm, sweet, woody-spicy aroma with excellent persistence. The bark oil is darker in colour, appearing deep brown, and has an intense spicy, warm, resinous fragrance that closely resembles cinnamon but is considerably stronger.
Major Chemical Constituents
Both the leaf and bark oils are composed primarily of cinnamaldehyde, which typically accounts for 75–90% of the oil. Other significant constituents include methyl eugenol, salicylaldehyde, and methyl salicylaldehyde, all of which contribute to the oil’s characteristic aroma and biological activity.
Safety Profile
Cassia essential oil is considered hazardous for topical use. It is a dermal toxin, skin irritant, skin sensitizer, and mucous membrane irritant. Because of its high cinnamaldehyde content, it should never be applied directly to the skin or used in aromatherapy massage. Even highly diluted applications require extreme caution, and the oil is generally not recommended for home aromatherapy use.
Aromatherapy Uses
Due to its significant risk of skin irritation and sensitization, Cassia essential oil is not recommended for aromatherapy or home use. Most aromatherapy references advise avoiding topical application entirely because it is considered one of the most irritating essential oils available.
Other Uses
Despite its safety limitations, Cassia essential oil is widely used in the pharmaceutical, food, and beverage industries. Its strong antimicrobial properties make it useful in products such as mouthwashes, toothpastes, gargles, and digestive tonics. It is also extensively used as a flavouring ingredient in confectionery, baked goods, alcoholic beverages, and soft drinks. Because of its dark colour and highly potent aroma, its use in perfumes and cosmetics is relatively limited.
