Jimmy I'm not sure if we can standardize this experiment or not and if the conclusions we draw at the end of it will even mean anything. It would be great to see everyone get similar results, but somehow there will always be outliers, and how would that skew the conclusions we want to draw from this. At this point, I'm not sure we have enough folks to even commit to doing this experiment for the results to be meaningful or not. The purpose of this experiment would be simply to see if we can overtake a starter at room temps and 2) if take overs are possible, if they occur more readily at room temps versus a cold fermentation maintenance. I have already determined that it isn't likely with cold fermentation. However we can still use the CF sample as a control.
I would suggest using IDY, ADY, or CY as the yeast source because they are relatively flavorless. If a new local yeast will overtake the starter, then it will be pretty evident as we are looking for a change in flavor of the starter. As I said, if anyone is to do this experiment, you will have to commit to feeding the starter at least once a day if not twice. You can't neglect a starter at room temps for 2-3 days, as it may create scenarios for take over and skew the results.
Of course you can use any existing sourdough starter if you want. Just be sure it is something you are very familiar with the flavor so that if a take over occurs, you will be able to detect it the flavor change.
For myself this is the plan. I have just started a CY starter, 10gm water + 10gm any flour (I'm using AP bleached) + a pinch of CY. Whatever you decide to use, it should be active in less than 12 hours. Once it becomes active, feed and maintain as any other starter at room temps of 75f.
Food source: will using bleached flour versus organic make a difference? I use cheap AP bleached flour to feed my starters because it's cheap. I am assuming bleached flours have less yeast in it. Anyone know if this is true or not?
Feeding schedule: I plan to feed my CY starter twice a day at 630 am and 630pm or there abouts. I will be dumping the starter and retaining only 1gm of the active starter to be mixed with 8gm of water and 12 gm of flour. This will give me approximately 8% starter seed in a ~68% hydration dough. At 75f room temps this will take approximately 12 hours to become active. This will ensure that if I miss feeding it by several hours, it should not overferment. You can choose any type of feeding routine but it should be reasonable. Yu can't really have a starter that becomes active in one hour and then not feed it for 24hours. This type of scenario may drastically affect the health of the starter, I don't know. What we are testing for here, is if a healthy starter that is maintained regularly can be overtaken by rogue yeast.
I will also be keeping a separate CY starter in the fridge that I will either feed weekly or not at all for the duration of the test. I don't know, I haven't decided yet so you guys can tell me what you want to see.
Room temps: everyone's room temp will differ slightly. I'm using 75f b/c my kitchen typically averages 75. If we can keep within 5f either way, I dont see that as having a significant impact on the results.
Length: 3-4 weeks or until the culture is overtaken if it happens sooner. I think even 2 weeks is plenty of time for a takeover to occur if it is to occur.
results: now suppose my starter develops acidic notes after 2 weeks. Would this neccessarily mean that a new strain of yeast has over taken it? I'm not sure it would. Could it be bacterial in nature? Can bacterial cause sourdough type of flavors? I'll leave this up to the the forum brainiacs to decide.
So does that sound simple enough? Can we get some folks to commit to this unscientific study. Again the goal of this is to simply see if....
1) starters can be overtaken from local yeasts. We will presume ths has happen if there is a drastic change in flavor of a raw starter.
2) if a starter take over is more likely at room temps versus cold temp maintenance.
Thoughts and suggestions? Do you guys consider this a fair, worthwhile, and meaningful experiment? Any takers besides Marlon and myself?