You can find xanthan gum in most commercially prepared sauces and dressings. In a home kitchen, xanthan gum aids the texture of gluten-free baked goods and can replace fat in low-fat recipes. You can make xanthan gum from microorganisms called Xanthomonas campestris that grow from the fermentation of yeast and sugar. Xanthan gum is water soluble. To keep it from lumping as soon as it touches liquid, mix the gum powder with sugar or oil before blending it with other ingredients.
Add 1 packet baker's yeast and 2 tbsp. water to a glass jar to make a yeast broth. Seal the lid on the jar and allow the yeast broth to sit for 24 hours.
Add 4 tbsp. corn syrup to the jar and replace the lid. Swirl the jar to combine the contents and allow it to sit at room temperature for five days. Swirl the jar every 30 minutes each day. On the fifth day the liquid should be thick and slimy.
Add 1/4 tsp. vodka to the jar and swirl it around. Vodka contains ethanol which recovers the xanthan and stops bacteria growth.
Place the silicone baking sheet on the sheet pan and spread the contents of the jar out in a thin layer on the silicone baking sheet. Place the pan in the oven and crack the door 2 inches. Set the oven to 200 degrees Fahrenheit and allow the xanthan paste to dry until it flakes when touched.
Peel the xanthan flakes off of the silicone baking sheet and place them in the coffee grinder. Process the xanthan gum flakes for about 2 minutes or until they become a fine powder. Store the xanthan in a clean airtight jar or zip-top bag.
If the xanthan is not kept airtight, it will absorb moisture from the air and lump. Put it back in the coffee grinder to remove the lumps.