Benzoin is a resin or balsam obtained from the bark of more than 125 species of deciduous trees belonging to the Styracaceae family. Commonly known as benzoin resin or styrax resin, this highly aromatic substance is sometimes referred to gum benzoin. That term is technically incorrect, however, since a gum is defined as containing a chemical structure consisting of strands of polysaccharides. To add to the confusion, benzoin is also the name given to an organic crystalline compound synthesized from benzaldehyde that has a completely different composition. The resin, on the other hand, yields a crystalline compound called benzoic acid.
To harvest this resin, triangular cuts are made into the bark of trees that have been cultivated and left to mature for at least six years. This causes the resin flowing within to pool toward and out of these incisions and harden very quickly upon coming into contact with the air. The quick drying factor, combined with the gravitational force of flow, often results in a teardrop-shaped knob of hard resin left dangling from the tree. Depending on the species of tree, the resin collected ranges in color from pale yellow to dark amber. Once tapped, most trees will continue to yield a flow of resin for another three years.
Due to its vanilla-like fragrance, the resin is important to the perfume industry as well as in the production of many kinds of incense. It is also a natural fixative and preservative and is used to “fix” the essential oils and other aromatic ingredients used to scent potpourri, and to increase the shelf life of many kinds of cosmetics. The resins used for these purposes are typically obtained from Styrax benzoin and Styrax tonkinensis. The former is found on the island of Sumatra, while the latter is cultivated in Vietnam, Cambodia, Laos, and Thailand. The yields from these trees are referred to as Sumatra and Siam benzoin, respectively.
A tincture is made from steeping the resin in an alcohol base for medicinal purposes. When administered as an inhalant, the tincture is reputed to be an effective natural cold remedy, as well as a treatment for bronchitis and other respiratory disorders. When applied topically, the tincture is considered an excellent home remedy for a variety of skin disorders, including acne, psoriasis, eczema, and rashes. It is also used as an antiseptic to treat cuts, wounds, blisters, and even cold sores and ulcerations of the mouth and gums.