Xanthan Gum

Function

Xanthan gum is a thickening agent produced by fermentation, it is used in molecular gastronomy to thicken sauces and dressings as well as to make fat-reduced, no-ice cream milkshakes that are just as thick.

Origin

Xanthan gum is a natural thickener derived from fermentation of glucose or sucrose by a bacterium, the Xanthomonas campestris. This very common bacterium is also responsible for frequent outbreaks of dark spots on the leaves of many vegetables, but it is harmless to humans.

Xanthan gum was discovered by the research team of Allene Rosalind Jeanes of the United States Department of Agriculture and has been marketed since the early 1960s.

Properties

The main property of xanthan gum is its ability to significantly increase the viscosity of a liquid. This effect is noticeable at concentrations of xanthan gum as low as 1%. The viscosity of xanthan gum solutions is variable. Indeed, it decreases during mixing and returns to its original balance when the product is put back to rest: this property is called "pseudo plasticity”. Xanthan gum is mainly used for its properties as a thickener and stabilizer, although it can also act as an anti-settling agent.

It dissolves easily in all liquids, hot or cold, and is stable under a wide range of temperatures and pH levels. Once heated, xanthan gum loses texture.

Combined with other types of natural gums, xanthan gum can be used to form gels that are resistant to acidic ingredients, whereas traditional gels like pectin and gelatine are not.

Industry applications

In the food industry, xanthan gum is very often found in salad dressings. It prevents oil separation by stabilizing the emulsion. Because of its pseudo plasticity, the product will be thick and uniform in its container, but will still be easily poured after stirring.

Xanthan gum is used in dairy products where it acts as a thickener and stabilizer. It prevents the formation of ice crystals in ice cream and provides a greasy feeling in the mouth to low fat dairy products.

The thickening properties of xanthan gum are also widely used in the cosmetic industry, where the additive thickens some creams and acts as a binding agent that ensures product consistency

Creative cooking applications

The value in using xanthan gum resides in its strong thickening power. Sauces thickened with xanthan gum are always light and creamy since the additive enhances the retention of air bubbles in the preparations. Adding xanthan gum to egg whites before beating improves the foam.

The anti-settling properties of xanthan gum can be favorably used in mixology, or the art of cocktails. For example it allows ingredients to remain suspended, such as pieces of fruit in molecular cocktails. It can also be used to reverse the components of a cocktail, whereby the heaviest alcohol becomes the element that floats.

Healthy cooking applications

Xanthan gum has a particularly unctuous effect in mouth without adding fat. It can thus replace some fats in sauces, smoothies and dips.

Xanthan gum can also be used by people allergic to gluten, to add volume and smoothness to breads, pastas and other dishes made with gluten-free flour.

Tips and tricks

During the spherification process, xanthan gum can be added to the alginate solution to make it easier to form large spheres, like ravioles.

Xanthan gum is a powerful thickener. If too much xanthan gum is added to a prepation, simply add water or another aqueous liquid to reduce viscosity of the mixture.

As xanthan gum loses some of its effectiveness when heated, tara gum can be substituted to provide smoothness to hot dishes.