Homemade Kombucha - Thank you for posting, will give it a try.
Turns out my problems may not have been dairy or gluten - I had a really bad infection of Helicobacter Pylori in my stomach (probably for years). I did the two-week triple treatment and am due for a follow-up check now (six weeks after ending the treatment). What a difference eradicating H. Pylori has made! I'm still using probiotics and prebiotics in supplement form and continuing dairy free and gluten free. I am doing small tests of re-introducing some dairy (0.3 ounces hard cheddar cheese, a very tiny bit of butter) and re-introducing some wheat products (a slice of whole wheat bread, a couple of crackers). So far, no adverse reaction to dairy and gluten after eradicating H. Pylori.
Gaijin...your response got me interested again in trying Kombucha. I'll try a commercial one first.