What is Xanthan gum?
[[File:Xanthan.svg|thumb|Xanthan]] [[File:Xanthan gum.JPG|thumb|Xanthan gum powder]] '''Xanthan gum''' is a [[polysaccharide]] (a complex form of [[sugar]]). It is added to certain foods, such as [[salad dressing]]s, to make them thicker. It is also added to [[cosmetics]] to keep the ingredients from separating. To make xanthan gum, workers add a kind of [[bacterium]], ''Xanthomonas campestris'', to [[glucose]] or [[sucrose]]. They let the mixture [[Fermentation|ferment]] for a while, and then add [[isopropyl alcohol]] to separate the polysaccharide from the mixture. They dry the polysaccharide, grind it into a powder, then add it to a liquid. The xanthan gum is then ready to use. ==History== [[Allene Rosalind Jeanes]] and her research team at the [[United States Department of Agriculture]] first discovered xanthan gum. The team was studying many biopolymers to see whether some of them were useful, and how they could be used. The Kelco Company was the first company to produce xanthan gum in the early 1960s. At that time, Kelco called xanthan gum by its brand name, Kelzan. Later, in 1968, xanthan gum was tested and declared safe to be used in food. The [[United States|USA]], [[Canada]], [[Europe]], and many other regions and countries now accept xanthan gum as a safe food additive. ==Uses== Xanthan gum is a very effective thickener. It is stable under a wide range of [[temperature]]s and [[pH]]. Only 0.5% of xanthan gum is added to most foods to thicken them. The thickening property of xanthan gum decreases when a food is mixed, shaken or chewed, but it thickens up again when the force is removed. This property is called pseudoplasticity. Sometimes this property can be very useful. For instance, the xanthan gum added to salad dressing makes the dressing thick enough to cling to a salad, but shaking the bottle of dressing makes it temporarily thin and easier to pour. [[Salad]] dressings and sauces contain xanthan gum. Even though xanthan gum is not an [[emulsifier]], it helps to keep an [[emulsion]] stable so t