The additive xanthan gum helps thicken certain foods, such as salad dressing. It's also used as an emulsifier to keep foods that naturally separate, such as oil and water, well-mixed. The additive is made when the Xanthomonas campestris bacterium ferments on sugar, creating a gel-like substance. While the U.S. Food and Drug Administration recognizes xanthan gum as safe, some people wish to eliminate food additives from their diets.

Xanthan gum is a type of sugar called a polysaccharide, and it's added to many commercially prepared baked goods to sweeten the foods. The additive is also an ingredient in certain gluten-free baked goods because it helps to stabilize the ingredients and make them doughy, which is what gluten would normally do. The addition of xanthan gum to gluten-free baked goods enables the ingredients to stick together so the foods can rise, if necessary, and bake normally.

Thickened dairy foods might also contain xanthan gum, according to Alistair M. Stephen and Glyn O. Phillips, authors of "Food Polysaccharides and Their Applications." Milk shakes, pudding, custard, whipped cream, yogurt, ice cream and sorbets are examples of some of the dairy foods that might contain xanthan gum. Xanthan gum is also added to these products because it helps manufacturers achieve the creamy texture that consumers want.

Many condiments contain xanthan gum to help achieve a creamy texture or to prevent certain ingredients from separating. For example, many salad dressings contain xanthan gum to help prevent the oil and the acid, usually vinegar, or water from separating as the product is stored on store shelves or in home refrigerators. Mayonnaise is another example, Stephen and Phillips note. Xanthan gum keeps the oil and water from separating, but it also gives the condiment a creamy texture. Certain jams, jellies and sauces, such as gravy, might also contain xanthan gum.

Some canned meat products, such as pate, might contain xanthan gum to help retain the creamy and thick texture consumers expect. Many powdered beverages contain xanthan gum, as well. The xanthan gum helps to sweeten the beverages and make them easy to mix with water. Pastry fillings and many frozen and ready-to-eat entrees contain xanthan gum, too. If you're determined to nix this additive from your diet, read food labels carefully to find items that don't contain xanthan gum.