Xanthan Gum is made from processed corn syrup. It's a gluten-free and low-carb powder which is great for thickening soups and sauces.
You can pick it up in the Quay Co-Op for about €8. That sounds a bit expensive, but you use so little of it that one tub will last a very long time. I'm only half way through mine and have had it about a year!