Xanthan gum is a kind of hydrophilic biological polysaccaride which is made from corn starch after processses of fermentation with xanthomonas campestais, extraction, drying and grinding. Benefited by its superior thickening and stabilizing effect,shear resistance and unnique preusdo-plasticity reheological property, xanthan gum is widely used in food, oil drilling, fine chemical, pharmaceutical and other fields.