<<Disclaimer: Verify this information before applying it to your situation.>> A couple of modifications I made to Laura's sourdough recipe came to mind which might be worth mentioning: I used milk instead of water, and half rice and half potato starch instead of only rice flour. These changes might be important. Lactobacillus growth is encouraged by the addition of milk- it will give a cleaner sourdough culture (once upon a time when I did microbiology, I plated my sourdough and found a clean co-culture of only yeast and lactobacillus- no other nasties). And lactobacillus has amylase activity which helps to break down the starch so yeast can use it, i.e. grow better. Potato starch has less amylopectin relative to amylose than rice flour so is more digestible. Potato has some soluble starch which is also more easily digestible. Lactobacillus also produces lactic acid, part of the "tang" of sourdough. I also neglected to mention the addition of more liquid with the second addition of flour and sugar- definitely wouldn't work without that! Didn't want you to be disappointed if you tried the directions "as is" and they didn't work as well as claimed! Mary T.