I gather that kefir grains are like big balls of mud, picking up lots of varieties of microbes. Over time, however, I’d guess that the number of strains might d

I gather that kefir grains are like big balls of mud, picking up lots of varieties of microbes. Over time, however, I’d guess that the number of strains might deteriorate due to more homogeneous growing medium and controlled kitchen environment. I’ve had a lot of kefir grains from different sources over the years, and many that you order online seem to be weak and not thrive. By contrast, I’d gotten some big healthy grains from a friend of a friend who’d been culturing them in raw milk in rural MT for a lot of years, and those things were monsters that grew large and divided often. They led me on an on- again off-again quest to find such excellent grains. I’ve heard of people introducing their grains to e.g. Icelandic skyr cultures, which results in the permanent colonization of the kefir grains by particular microbes. The skyrified kefir being qualitatively different. I could see getting a lab strain of reuteri and similarly training kefir grains to incorporate this as part of the colony.