Xanthan gum is glucose that has been fermented by the xanthomonas caperstis bacteria. It has no sugar, fat or protein, but has 2.6 g of fiber per teaspoon. Xanthan gum is used by the cosmetics and food industries as a thickener, emulsifier and stabilizer. It makes salad dressings that are glossy and cling to your salad without sacrificing flavor, according to Aki Kamozawa, author of "Ideas in Food: Great Recipes and Why They Work." It also allows you to reduce or eliminate entirely the amount of oil you add to your salad dressing.
Blend all the dry ingredients except xanthan gum in the blender for a few seconds until well combined.
Add the tomato paste, vinegar, water and oil and blend for a few seconds until the mixture is well combined.
Add the xanthan gum and blend again for 10 seconds.
Pour the mixture into a pint jar and cover. Store in the refrigerator. Allow the flavors to blend for a day before using.