Xanthan Gum is a light yellow to white flowable powder with a slight odor. Easily soluble in cold and hot water, neutral in solution, resistant to freezing and thawing, insoluble in ethanol. It is dispersed and emulsified in water to become a stable hydrophilic viscous colloid.
Xanthan gum has the following 9 properties:
1. Typical rheological properties:
As the shear rate increases, the colloidal network is destroyed, resulting in a decrease in viscosity and thinning of the glue, but once the shear force disappears, the viscosity can be recovered, so it has good pumping and processing performance. Using this feature to add xanthan gum to the liquid that needs to be added with a thickener, not only does the liquid flow easily during the transportation process, but also restores the required viscosity after resting, so it is widely used in the beverage industry.
2. High viscosity at low concentration:
The viscosity of the liquid containing 2% to 3% xanthan gum is as high as 3 to 7 Pa s. Its high viscosity makes it have broad application prospects, but at the same time it brings trouble to the post-processing in production. Monovalent salts such as 0.1% NaCl and divalent salts such as Ca and Mg can slightly reduce the viscosity of low glue solution below 0.3%, but can increase the viscosity of higher concentration glue solution.
3. Heat resistance:
The viscosity of xanthan gum has almost no change in a wide temperature range (-98~90℃). Even if it is kept at a high temperature of 130 °C for 30 min and then cooled, the viscosity of the solution does not change significantly. The viscosity of the glue did not change after multiple freeze-thaw cycles. In the presence of salt, the solution has good thermal stability. If a small amount of electrolyte such as 0.5% NaCl is added under high temperature conditions, the viscosity of the glue can be stabilized.
4. Acid and alkali resistance:
The viscosity of an aqueous solution of xanthan gum is almost independent of pH. This unique property is not possessed by other thickeners such as carboxymethyl cellulose (CMC). If the inorganic acid concentration in the glue solution is too high, the glue solution will be unstable; at high temperature, hydrolysis of polysaccharides by acid will occur, thus causing the glue solution viscosity to decrease. If the content of NaOH is more than 12%, xanthan gum will gel or even precipitate, and if the concentration of sodium carbonate exceeds 5%, it will also cause gelation.
5. Anti-enzymatic hydrolysis:
Due to the shielding effect of the side chain, the xanthan gum skeleton has the peculiar ability not to be hydrolyzed by enzymes.
6. Compatibility:
Xanthan gum is miscible with most common
Food Thickener solutions, especially after being miscible with alginate, starch, carrageenan and carob gum, the viscosity of the solution increases in the form of superposition. It exhibits good compatibility in aqueous solutions in the presence of various salts. However, high-valent metal ions, high pH will make it unstable, adding a complexing agent can prevent the occurrence of incompatibility.
7. Solubility:
Xanthan gum is easily soluble in water, but insoluble in polar solvents such as alcohol and ketone. It is readily soluble in water over a very wide range of temperature, pH and salt concentration, and its aqueous solutions can be prepared at room temperature with minimal air entrainment during agitation. If xanthan gum is mixed with some dry substances such as salt, sugar, monosodium glutamate, etc. in advance, then moistened with a small amount of water, and finally mixed with water, the prepared glue will have better performance. It can be dissolved in many organic acid solutions and has stable performance.
8. Dispersion:
The bearing capacity of 1% xanthan gum solution is 5N/m2, which is an excellent suspending agent and emulsion stabilizer in food additives.
9. Water retention:
Xanthan gum has a good water retention and preservation effect on food.
