Xanthan Gum was discovered during the 1950s by American scientists and is essentially the byproduct of a bacterial fermentation. Like yeast fermentation produces alcohol and carbon dioxide, Xanthan Gum is produced from fermented Xanthomonas Campestri. Like in bread and alcohol production heat is used to kill off the bacteria after the fermentation and then the gum is collected and dehydrated.
Xanthan Gum, like other additive must then be hydrated in water. However, unlike with other additives Xanthan Gum does not require heat although it can withstand a range of temperatures as well as pH and the presence of salts and alcohol up to 60%.
Xanthan Gum is a thickener and stabilizer, but it does not form gel. Xanthan Gum can be used to stabilize emulsions and give sauces a thick and cream texture. One interesting fact about Xanthan Gum is its ability to change viscosity. When agitated, a mixture containing Xanthan Gum, will become liquid. When allowed to rest it will then become more viscose or thicken.
Aside from emulsions and sauces Xanthan Gum can be used in milkshakes to produce high fat mouth feel without the presents of high fat milk and in ice cream, where it prevents the development of ice crystals and makes for a creamier texture.