What it does
The chain has side units that fold back along the backbone and protect it, which is why xanthan tolerates acid, salt, heat and enzymes that would destroy most other gums. In solution it forms a weak network that collapses under shear and rebuilds the moment shear stops. That behaviour is shear thinning, and it is why a dressing pours from the bottle and then sits on the salad instead of running off it.
Where it works
Dressings, sauces, anything acidic, anything high in salt, anything that has to suspend particles at rest. Also gluten free bakery, where it does part of the job the missing gluten network did.
Where it does not
Its mouthfeel is distinctive and can read as slimy at higher levels, particularly in a drink. It is also not a gelling agent on its own.
What it interacts with
Locust bean gum and konjac, synergistically and strongly enough to form true gels. Guar, additively. Starch, where it protects viscosity through processing the starch alone would not survive.
