What is xanthan gum
Xanthan gum, commonly known as corn gum or Hansheng gum, is a complex polysaccharide produced by fermentation of sugars (glucose, sucrose, lactose) by Xanthomonas campestris in wild rapeseed.
Xanthan gum is usually made from corn starch and is mainly made from carbohydrates by Brassica napus Xanthomonas campestris. Through aerobic fermentation biotechnology, 1,6-glycosidic bonds are cut off, branching chains are opened, and straight chains are synthesized by pressing 1,4-bonds to form an acidic extracellular polysaccharide.
Xanthan gum is a white or light yellow powder with excellent thickening, suspension, emulsification, and water solubility, as well as good thermal and acid-base stability, making it widely used in various foods.
Xanthan gum can dissolve quickly in water and has good water solubility. Especially soluble in cold water, it eliminates the need for complicated processing and is convenient to use.
However, due to its strong hydrophilicity, if water is added directly but not stirred thoroughly, the outer layer will absorb water and expand into micelles, which will prevent water from entering the inner layer and affect its effectiveness. Therefore, it is necessary to pay attention to correct use.
Yellow gum dry powder or mixed with salt, sugar and other dry powder excipients, then slowly added to the stirring water to make a solution for use.
Xanthan gum solution has the characteristic of low concentration and high viscosity (the viscosity of a 1% aqueous solution is 100 times that of gelatin), making it an efficient thickener.
Xanthan gum aqueous solution exhibits high viscosity under static or low shear conditions, and exhibits a sharp decrease in viscosity under high shear conditions, while the molecular structure remains unchanged.
The viscosity of xanthan gum solution does not change significantly with temperature changes. The viscosity of xanthan gum aqueous solution remains almost unchanged between 10-80 ℃, and even low concentration aqueous solutions exhibit stable high viscosity over a wide temperature range. 1% xanthan gum solution (containing 1% potassium chloride) is heated from 25 ℃ to 120 ℃. Its viscosity only decreases by 3%.
Xanthan gum solution is very stable to acidity and alkalinity, and its viscosity is not affected between pH 5-10. There is a slight change in viscosity when pH is less than 4 and greater than 11. Within the range of PH3-11, the maximum viscosity is within 10% of the minimum value. Xanthan gum can dissolve in various acid solutions, such as 5% sulfuric acid, 5% nitric acid, 5% acetic acid, 10% hydrochloric acid, and 25% phosphoric acid. These xanthan gum acid solutions are quite stable at room temperature and the quality of the product remains unchanged for several months.
Xanthan gum can also dissolve in sodium hydroxide solution and has thickening properties. The resulting solution is very stable at room temperature. Xanthan gum can be degraded by strong oxidants such as perchloric acid and persulfuric acid, and the degradation accelerates with increasing temperature.
Xanthan gum solution can be mixed with many salt solutions (potassium salts, sodium salts, calcium salts, magnesium salts, etc.), and its viscosity is not affected. Under high salt concentration conditions, even in saturated salt solutions, its solubility is maintained without precipitation and flocculation, and its viscosity is almost unaffected.
The stable double helix structure of xanthan gum endows it with strong antioxidant and anti enzymatic abilities. Many enzymes such as proteases, amylases, cellulases, and hemicellulases cannot degrade xanthan gum.