Balsam is the resinous exudate (or sap) which forms on certain kinds of trees and shrubs. Balsam (from Latin balsamum "gum of the balsam tree", ultimately from a Semitic source such as Hebrew basam, "spice", "perfume") owes its name to the biblical Balm of Gilead.
Balsam is a solution of plant-specific resins in plant-specific solvents (essential oils). Such resins can include resin acids, esters, or alcohols. The exudate is a mobile to highly viscous liquid and often contains crystallized resin particles. Over time and as a result of other influences the exudate loses its liquidizing components or gets chemically converted into a solid material (i.e. by autoxidation).[1]
Balsams often contain benzoic or cinnamic acid or their esters.[2][3] Plant resins are sometimes classified according to other plant constituents in the mixture, for example as:[2]
Usually, animal secretions (musk, shellac, beeswax) are excluded from this definition.
The Balsam of Matariyya was a substance famous as a panacea among physicians in the Middle East and Europe during the Antique and Medieval periods. The substance has long been used as a medicine, with early references to the substance recorded as far back as 285 BC. The Balsam of Matariyya was said to be derived from an Egyptian plant and is sometimes also referred to as the balm of Gilead or the balm of Mecca.[4]
Some balsams, such as Balsam of Peru, may be associated with allergies. In particular, Euphorbia latex ("wolf's milk") is strongly irritant and is cytotoxic.
