Researchers in Germany found that microbes love the microscopic fibers in coffee. These soluble coffee fibers are food for bacteria and make the beneficial Bacteroides microbes experience up to 60% increase in growth. Soluble fibers, which are prebiotics, do so many things. They improve insulin sensitivity, allow you to absorb more calcium, convert some plant fibers into Vitamin A, and much, much more. This is the same recipe you would use when you are making regular kombucha except you use coffee instead of tea. It gets super bubbly! Once you use your scoby for coffee kombucha, you can't use it again in regular kombucha tea.