Xanthan gum is found occasionally in pet products, most commonly in wet foods and periodically in sauces and gravies, milk replacers and other liquid supplements. While one can find this ingredient in the specialty grocery aisle for vegetarian and gluten-free dietary needs, it is not what one would consider mainstream. So, what is this ingredient, why are we finding it in these specialized applications and is it safe for our dogs and cats?
Generally speaking, xanthan gum is a polysaccharide exudate resulting from fermentation of Xanthomonas campestris grown on various carbon substrates. This organism occurs naturally; most commonly you'd find it as the black rot fungi on the cruciferous vegetables you've had in your refrigerator a bit too long. While unsightly, it's not harmful in itself. The commercial organisms, in contrast to these wild-type fungi, have been selected to grow prolifically on specific carbon compounds--everything from whey to sucrose. The property that is primarily being targeted is the X. campestris' ability to produce a particular polysaccharide gel or gum as its protective coating.
