Origins
Gum Arabic, like many other plant-based gums, is derived from different species of acacia.
Despite its wide distribution, gum arabic can be differentiated according to its origin. Most gum arabic is grown in the Nile, Somalia, Morocco, Australia and Senegal.
It is mainly derived from two types of acacia plant, a member of the legume family, and is sometimes referred to as acacia powder, acacia gum, or acacia resin.
There are at least 400 different species of acacia grown in tropical and subtropical regions to produce the gum (mainly in Australia and Africa). In particular, Sudan holds the record for gum arabic production, with production accounting for 50% of world production.
How it is extracted: gumming and tapping
Gum arabic can be obtained in two ways: through gumming or by tapping.
Gumming
90 % of arabic gum is produced naturally through the process of “gumming” by the two sub-Saharan species acacia Senegal and acacia Seyal.
In this case, sap is produced spontaneously by the plant in response to temperature changes or to eliminate pests. The tree then begins to exude a sticky substance to repair the broken bark. In fact, this substance can be secreted as a result of wind, drought, transpoarabinogalactan silica (AGP) particles with a globular or branched structure replaced and carried by the wind, human cuts, scratches from wild animals, insects and parasitic plants, and other factors. In essence, the gum protects the tree from evaporation, which is detrimental to its survival.
This process makes this material even more natural because it is extracted in a completely natural way.
Tapping
Tapping, on the other hand, is a technique that involves cutting a strip of bark 2 to 3 cm wide and up to 1 m long with a knife, dividing it transversely at the base of a branch and pulling it upward by hand as much as possible.
The tissue is torn off, and a scar bulge forms at the edge of the wound, from which the gum exudes three weeks later. Through this process it is possible to obtain balls the size of a fist. The exudation process is most common in October, November and December, when trees lose half their foliage. Six to eight harvests are made each year, and the production season usually ends in March or April.
The side of the branch incision must be changed each year, with up to four cuts around the branch. After that, the branch must be changed. Four to ten branches are used each year, depending on the size of the tree and its degree of branching.
In general, wounds on the trunk-and thus secretion of sticky latex-are more common in mature or old trees with drier bark. Acacia gum production increases as trees age or grow in harsh conditions, such as nutrient-poor soils or extreme drought.
Freshly secreted bark gum is soft but hardens quickly in the open air. When it hardens, it takes the form of irregular, rounded flakes of light or amber color. At this point it is ready to be harvested, purified and sold.
It is also available in the form of white or yellowish-white flakes, granules, crystals or powders, as well as as a dried and spray-dried substance.