Pour milk into a saucepan, stir in guar gum and begin to slowly heat the milk until it begins to boil. Reduce heat and simmer for 5-6 minutes.
Remove from heat and let cool to 108°F. Transfer to large glass jar. Stir in contents in probiotic capsules into milk mixture (discard gelatin caps) using a sterilized spoon.
Cover jar with cheesecloth. Leave in a warm spot in your kitchen (not hot), for 12 hours. Stir and taste contents. If you would like it tangier, leave it out for an additional 6-12 hours. Stir well and store in the fridge when desired tanginess is achieved. Add keto friendly sweetener if desired to taste.