Balsam is the resinous exudate (or sap), which forms on certain kinds of trees and shrubs. Balsam (from Hebrew bosem בֹּשֶׂם, "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).
Some authors require balsams to contain benzoic or cinnamic acid or their esters. Plant resins are sometimes classified according to other plant constituents in the mixture, for example as:
pure resins (guaiac, hashish),gum-resins (containing gums/polysaccharides),oleo-gum-resins (a mixture of gums, resins and essential oils),oleo-resins (a mixture of resins and essential oils, e. g. capsicum, ginger and aspidinol),balsams (resinous mixtures that contain cinnamic and/or benzoic acid or their esters),glycoresins (podophyllin, jalap, kava kava),fossile resins (amber, asphaltite, Utah resin).Usually, animal secretions (musk, shellac, beeswax) are excluded from this definition.
Acaroid resin (Xanthorrhoea sp.)Acouchi balsam (Protium sp.)AmmoniacumAsafoetida (Laser)Balm of GileadBalm of MeccaBalsam of PeruBalsam of ToluBisabolBdelliumBenzoin resinBukhoorCabreuva balsam (Myrocarpus frondosus, Myrocarpus fastigatus)CamphorCanada balsamChinese lacquer (Japanese lacquer)Copaiba balsamCopalCorneiba balsam (Schinus terebinthifolius or Lithraea brasiliensis)DamarDragon's blood (Calamus draco)ElemiFrankincense (Olibanum)GalbanumGuayac (Guaiacum officinale)GuggulGurjun balsamImbauba balsam (Cecropia adenopus)LabdanumMasticMyrrhObira balsam (Apocynaceae)OpopanaxUmiri balsam (Humiria floribunda)Rosin (Colophony)SagapenumSandaracSarcocollaStorax balsamTurpentineVenice turpentine (Larch turpentine) (Larix europaea)Wallaba balsam (Eperua sp.)Some balsams, such as Balsam of Peru, may be associated with allergies. In particular, Euphorbia latex ("wolf's milk") is strongly irritant and cytotoxic.
