Xanthan gum is a polysaccharide that belongs to a family of substances known as hydrocolloids. These polysaccharide have the ability to form a gel and bind many times their weight in water, making them very valuable as a food additives.
With the help of the bacteria Xanthomonas campestris, xanthan gum can be made using carbohydrates from corn, wheat, dairy, or soy. Xanthan gum is named after this particular species of bacteria, which is required for its production.
How is Xanthan Gum Made?
Xanthan gum is formed by Xanthomonas campestris during the process of fermentation. When the bacteria is introduced to a nutritive solution containing carbohydrates (from corn, wheat, dairy, or soy), fermentation begins and the polysaccharide xantham gum is produced as a byproduct. The xanthan gum is then precipitated from the solution using isopropyl alcohol, dried, and milled into a powder so that it can be added to food and other products.
Xanthan gum was discovered by the United States Department of Agriculture through research conducted by Allene Rosalind Jeanes. Xanthan gum was approved for use as a food additive in the United States in 1968 and is now a common food additive throughout the world.
Xanthan gum is usually made from grains and other plants because they contain glucose an sucrose, two sugars that X. campestris can naturally ferment. A special strain of the X. campestris bacteria was developed that can ferment lactose, a major component of whey. Whey, a byproduct of the cheese process, is now used as an inexpensive source of carbohydrate for xanthan gum production.
How is Xanthan Gum Used?
When xanthan gum is combined with water, it binds and forms a highly viscous gel. This viscosity makes xanthan gum useful in enhancing the appearance, texture, and stability of food.
The gelling action of xanthan gum is often used in low-fat salad dressings to stabilize and form an emulsion in place of fats and oils. Xanthan gum also acts similarly to fat in frozen desserts by preventing the formation of large ice crystals. This creates a softer, smoother mouth feel in the final product.
Xanthan gum’s thickening power is also used to create body in food. Products like pudding, yogurt, and whipped cream benefit from the addition of xanthan gum to create thickness and improve the appearance and texture.
Xanthan gum’s role in sauces is not only to provide body and thickness, but also to suspend ingredients such as spices and herbs. The gelling action prevents the components of sauces from separating out during storage. In the same manner, xanthan gum prevents water from separating out and pooling on top of sauces like ketchup and mustard, which is often seen as undesirable to consumers.
Due to its non-toxicity and great thickening power, xanthan gum is also used in many non-food products. Xanthan gum can be found in shampoos, soaps, and other beauty products.
Availability of Xanthan Gum
Xanthan gum is generally only available commercially although recently it has been popping up on the shelves of health food stores and other specialty retailers. Demand for the thickening power of xanthan gum has increased on the consumer level as gluten free and vegan diets have become more popular. Xanthan gum is often used in recipes to create thickness where wheat or animal products would normally be used.