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Product Overview
Xanthan Gum, also known as Gum Arabic, is a widely used microbial polysaccharide produced by fermenting carbohydrates (such as corn starch) with Xanthomonas campestris. It features unique rheological properties, good solubility in water, stability to heat and acid/base conditions, and excellent compatibility with various salts. It serves as a thickener, suspending agent, emulsifier, and stabilizer and finds applications in over 20 industries including food, petroleum, and pharmaceuticals. It is currently the most extensively produced and widely used microbial polysaccharide in the world.
Production Process
Xanthan Gum is produced by strains of the genus Xanthomonas. The primary industrial strain used is Xanthomonas campestris, although other strains like Xanthomonas soyae, Xanthomonas malvacearum, and Xanthomonas carotae can also be used. The production process is influenced by factors such as medium composition, culture conditions (temperature, pH, dissolved oxygen), reactor type, and operational mode (continuous or batch).
Xanthan Gum Extraction: Recovering the product from the fermentation broth is relatively costly. Typically, the final fermentation broth contains: Xanthan Gum: 10–30L, Cells: 1–10g/L, Residual Nutrients: 3–10L, and other metabolites. Due to the high concentration of Xanthan Gum, the solution is highly concentrated, making extraction challenging. It is recommended to dilute first. Main extraction steps include cell precipitation, Xanthan Gum precipitation, dehydration, drying, and grinding.
Benefits and Functions
Thickener, suspending agent, emulsifier, stabilizer.
Xanthan gum is currently the most advanced biopolymer worldwide, combining thickening, suspending, emulsifying, and stabilizing properties. The number of acetyl groups at the end of its molecular side chains greatly impacts its performance. Xanthan gum exhibits typical properties of long-chain polymers but contains more functional groups, showing unique properties under specific conditions. Its conformation in aqueous solutions is diverse, displaying different characteristics under varying conditions.
- Suspension and Emulsification
Xanthan gum effectively suspends insoluble solids and oil droplets. Its molecules can form large, band-like helical copolymers, creating a fragile, gel-like network structure that supports the shape of solid particles, droplets, and bubbles. This results in strong emulsification stability and high suspension capacity.
- Excellent Water Solubility
Xanthan gum dissolves quickly in water and has excellent water solubility. It can even dissolve in cold water, simplifying the processing and making it user-friendly. However, due to its strong hydrophilicity, if it is added directly to water without sufficient stirring, the outer layer may swell into a gel, preventing water from penetrating the inner layer and affecting its performance. Therefore, correct usage is crucial. Xanthan gum powder should be mixed with salts, sugars, or other dry ingredients and then slowly added to stirring water to make a solution.
- Thickening
Xanthan gum solutions have a high viscosity at low concentrations (a 1% solution is 100 times more viscous than gelatin), making it an efficient thickener.
- Pseudoplasticity
Xanthan gum solutions exhibit high viscosity under static or low shear conditions. Under high shear, the viscosity dramatically decreases, but the molecular structure remains unchanged. When the shear force is removed, the viscosity immediately returns to its original level. The relationship between shear force and viscosity is highly adaptable. Xanthan gum's pseudoplasticity is particularly effective for stabilizing suspensions and emulsions.
- Thermal Stability
The viscosity of Xanthan gum solutions remains relatively stable with temperature changes. Unlike most polysaccharides, which change viscosity with heating, Xanthan gum solutions maintain consistent viscosity between 10-80°C. Even at low concentrations, the solution remains highly viscous across a wide temperature range. For example, a 1% Xanthan gum solution (containing 1% potassium chloride) only experiences a 3% decrease in viscosity when heated from 25°C to 120°C.
- Acid-Base Stability
Xanthan gum solutions are highly stable to acids and bases, with viscosity unaffected between pH 5-10. There is only slight viscosity variation at pH levels below 4 or above 11. Within the pH range of 3-11, viscosity changes by less than 10%. Xanthan gum dissolves in various acid solutions, such as 5% sulfuric acid, 5% nitric acid, 5% acetic acid, 10% hydrochloric acid, and 25% phosphoric acid, and remains stable at room temperature for months without quality degradation. It also dissolves in sodium hydroxide solutions, retaining its thickening properties and stability at room temperature. Xanthan gum can be degraded by strong oxidizers like perchloric acid and persulfate, with degradation accelerating at higher temperatures.
- Salt Stability
Xanthan gum solutions can mix with many salt solutions (potassium, sodium, calcium, magnesium salts) without affecting viscosity. Even in high salt concentrations or saturated salt solutions, it remains soluble without precipitation or flocculation, with minimal impact on viscosity.
- Enzymatic Stability
The stable double-helix structure of Xanthan gum provides strong resistance to oxidation and enzymatic degradation. Many enzymes, including proteases, amylases, cellulases, and hemicellulases, cannot degrade Xanthan gum.
Applications:
Due to its unique properties, Xanthan gum has a wide range of applications in food, petroleum, pharmaceuticals, daily chemicals, and more. Its high commercialization and extensive application range surpass those of any other microbial polysaccharide.
- Food Industry: Xanthan gum is added to many food products as a stabilizer, emulsifier, suspending agent, thickener, and processing aid. It controls the rheology, structure, flavor, and appearance of products, and its pseudoplasticity ensures a good texture. It is widely used in salad dressings, bread, dairy products, frozen foods, beverages, seasonings, brewing, confectionery, pastries, soups, and canned foods. In recent years, concerns about calorie content have led consumers to prefer Xanthan gum, which is not directly degradable by the human body. Additionally, a 1985 report from Japan indicated that Xanthan gum is one of the most effective anti-cancer agents among eleven food additives tested.
- Daily Chemicals: Xanthan gum's high hydrophilicity makes it a good surfactant with antioxidant and anti-aging properties. Therefore, it is a major functional ingredient in most high-end cosmetics. It is also used in toothpaste to provide thickening and stabilization, reducing surface wear on teeth.
- Medical Applications: Xanthan gum is a popular component in microencapsulation for controlled drug release. Its strong hydrophilicity and water retention have various medical uses, such as forming protective water films to prevent skin infections and alleviating thirst after radiation therapy. Research has also shown that Xanthan gum enhances fluid immune function in mice.
- Industrial and Agricultural Applications: In the petroleum industry, Xanthan gum's strong pseudoplasticity allows a low concentration (0.5%) solution to maintain viscosity and control rheological properties in drilling fluids. It reduces viscosity at high-speed drilling and maintains high viscosity at stationary drilling sites to prevent well collapse. Its excellent salt and heat resistance makes it widely used in marine and high-salinity environments for drilling and as an oil recovery agent to reduce dead oil zones and increase oil recovery rates.
Packaging and Storage:
Storage Conditions: Store in a sealed, light-proof container away from high temperatures in a dry, cool, and well-ventilated place.
Packaging: Bulk: 25kg cardboard drums; Samples: 1kg aluminum foil bags; Custom packaging available.
Transportation: Express or logistics. Domestic express delivery within three days; logistics within five days. Quotes generally include domestic shipping costs.
Shelf Life: Two years.
