Did you know (according to Wikipedia) Xanthan gum is a polysaccharide, derived from the bacterial coat of Xanthomonas campestris, used as a food additive and rheology modifier (A what now?), commonly used as a food thickening agent (in salad dressings, for example) and a stabilizer (in cosmetic products, for example, to prevent ingredients from separating). It is produced by the fermentation of glucose, sucrose, or lactose by the Xanthomonas campestris bacterium. Now whilst all of these things are great, I can't recall the last time a recipe called for Xanthan Gum (at least a home-made one) and I certainly don't recall any TV chef exclaim - when buying Xanthan Gum you MUST use Bob's Red Mill - it's simply the best!!! But it really is a GREAT rheology modifier and for that it gets FOUR STARS! The fifth star separated.