Xanthan gum appears as a white or pale yellow powder with no distinct odor and is readily soluble in water. Upon dissolution, it forms a highly viscous colloidal solution classified as a non-Newtonian fluid; it exhibits a significant thickening effect even at low concentrations. At room temperature, the viscosity of a 1% aqueous solution typically ranges between 4,000 and 12,000 mPa·s, a parameter that can be adjusted to suit various specific applications. Its pH value falls within the range of 6.0 to 8.0; loss on drying does not exceed 15%, ash content remains within 4%, and moisture content is generally below 12%. The carboxylate groups-present in the form of sodium, potassium, or calcium salts-impart excellent heat resistance, acid-alkali stability, and salt tolerance to xanthan gum, ensuring its stable performance across food, pharmaceutical, and industrial applications.
Food-grade and pharmaceutical-grade xanthan gum are subject to strict requirements regarding microbial content: the total viable count must not exceed 1,000 CFU/g, and mold and yeast counts must not exceed 100 CFU/g. Furthermore, they must be free from pathogenic bacteria such as *E. coli* and *Salmonella*. Heavy metal content is strictly controlled, with lead levels not exceeding 5 mg/kg and arsenic levels not exceeding 3 mg/kg. Xanthan gum exhibits low toxicity and causes no significant irritation to the skin or eyes. Its solutions effectively stabilize suspended particles and emulsion systems while maintaining resistance to heat, acids, alkalis, and salts, making it highly suitable for use in foods, beverages, cosmetics, pharmaceutical preparations, and various industrial products.
