Structure
Xanthan gum: viscosifying and stabilizing agent

Xanthan gum is a substance secreted by bacteria (see History box). It's a huge molecule. Its molecular mass is estimated at between 1.5 × 10⁶ and 5 × 10⁶ daltons, or 1.5 to 5 t/mol! Its approximate and average gross formula is as follows:

(C₆₇H₁₀₂O₅₆)_nn = 830 to 2,800

• The primary structure of xanthan gum consists of a main cellulose chain of β-d-glucose monomers linked together by o-glycosidic bonds (1-4). This chain carries a triosidic side branch every 2 glucose. This branch consists of an α-d-mannose linked to the main chain by osidic linkage (1-3), a β-d-glucuronic acid linked to the 1^er mannose by osidic linkage (1-2) and a β-d-mannose linked to glucuronic acid by osidic linkage (1-4). The 1^er mannose is most often acetylated in position 6, and the 2nd mannose can be pyruvylated...