I haven't been on the forum in quite a while, but I was immediately drawn to this thread. I've experimented with natural and ambient culturing in the past and I'm interested in hearing other's experiences. I dig up the technique I've used for years for what I call "Old School Chevre." A couple of years ago I wrote it down. I never would have thought to do that until I started taking good notes on my main cheesemaking efforts:
CA137a. 7/1/13. Old school chevre.
2 qts. Raw Nigerian Dwarf goat milk. Morning milking
Leave at room temp . (On 7/1 started 70F rose to 84F)
Culture for 18 hrs. or until curd and whey have perfectly separated.
Ladle curd into cheesecloth. Tie corners. hang and drain 12hrs. Mix with 3/4 tsp. salt.
It's not very scientific, but I've made and eaten cheese from this 'recipe' more than two dozen times and I'm still here to tell you about it. The cheeses from this method have yielded varying results, surely based on the season, stage of lactation, length of coagulation, but mostly from the ambient cultures levels present that day. I too might have yogurt and kefeir culturing, bread rising, and sauerkraut bubling, among other things in the same kitchen on any given morning.
I've had results that ranged from delightful, through not bad and 'meh', down to the rare 'yuck.' I do recall a couple of occasions when the resulting 'cheese' want straight to the chickens or pigs because it smelled or looked a little off. I really don't think it would have made me sick, but why take a chance on something that I figured wouldn't taste good anyway.
The flavor has sometimes been more or less tart than I find in my chèvres from store-bought cultures. Go figure. I always got a good curd set, but if the culture had remained thin and milky I'd have dumped it. On occasion I would add a drop or two of calf rennet at the onset of I had some prepared heading into another make.
I never thought to reserve a bit at some stage to culture another make. That idea is intriguing. Successive cultures would bring the dominant strains to the forefront. I have however made renneted pressed cheeses using no starter culture, only raw goats milk. Those results were good for me so far.
I don't use these methods the majority of the time. Usually I am aiming for a specific result and utilize the control of commercial cultures. Once in a while though, it is fun to surrender to the whims and serendipity of nature in the raw.
By the way Tim T, how did your natural jack turn out?