Xanthan gum is a polysaccharide used as a food additive and rheology modifier (Davidson ch. 24). It is produced by a process involving fermentation of glucose or sucrose by the Xanthomonas campestris bacterium. Xanthan gum burns relatively hot, especialy when mixed with nitrates. It is used in some stars as a fuel and to regulate the burn rate. Xanthan gum must be used sparingly due to the fact that it will create molten slag in nozzles (dross), and it will become molten on the out side of stars, preventing them from burning properly, reversing the positive effects the gum adds. Xanthan gum is typically used in stars that spark or glitter such as Penny stars, and will brighten the sparks but shorten their life. Xanthan gum can be bought at a grocery store.