I made curds and whey from raw milk and had the same results as the first person in this thread, that is it took longer than 4 days and by then I was worried about how safe it was. I threw out the curds because they smelled bad, but I put the whey in the fridge and it's still there. It's been a month and I've been too scared to use it. I would really like to know for sure that this process is not growing all kinds of nastiness, because I would like to use the whey in the formula recipe from "Nourishing Traditions". But I have been using commercial formula because of my concern over this nasty smelling liquid thats supposed to be so good for us. That last suggestion of making whey from yogurt sounds safer to me. I used to make yogurt "cheese" in the fridge all the time and just pitched the whey. Can you suggest references citing the bacterial safety of the whey? Thank you!