Water for Starter

[crawsdaddy]

I don't use my tap water for pizza because of the heavy chlorine and fluorite added to tap water here. I used Dansani purified water until about a year ago when I switched to Evian for its mineral content and also used it for the starter. During the last year, it has taken an hour or two longer for the starter to double in size and there was almost no activity for the first hour or two. I switched feeding flours, changed the room temperature etc in an attempt to speed up activity of starter. Last week I switched back to Dasani in the starter to see if it would make a difference--and lo and behold the starter is back to the levels before I switched to Evian. Maybe this is purely coincidental or maybe the minerals in Evian slowed the activity.  For whatever this observation is worth.

[Bill/CDMX]

Some starters are particularly sensitive to the pH of the water. Do you have a way to measure? 

[crawsdaddy]

Some starters are particularly sensitive to the pH of the water. Do you have a way to measure?

I guess the pool testing kit will do that but I don't know how to do that. Attached is photo of stuff included in water.

[Bill/CDMX]

I'd try the following experiment to see if it is really the water:

Activate two identical samples, the only difference being that each uses a different brand of room temp water. Keep them side-by-side so they are exposed to the same temps. Measure expansion at regular intervals. Take some photos for the audience.

[crawsdaddy]

I'd try the following experiment to see if it is really the water:

Activate two identical samples, the only difference being that each uses a different brand of room temp water. Keep them side-by-side so they are exposed to the same temps. Measure expansion at regular intervals. Take some photos for the audience.

Bill see attached photos, the one is clearly ahead of the other after 4 hours. The one is fully 3/4" taller than the other. I measured the amount of beginning starter and the amount of water and flour added to each. I think one could conclude there is a possibility that type of water influences the speed at which starter becomes fully active however I would be reluctant to make a definitive statement because I am not sure I have completely eliminated every variable.

[Bill/CDMX]

however I would be reluctant to make a definitive statement because I am not sure I have completely eliminated every variable.

If everything is the same except the brand of water, what other variables are the source of your doubt? All measurements are by weight, right?

[crawsdaddy]

The amount of starter was not by weight but by volume, flour and water added were by weight. I also think that the amount of time the yeast is stirred could be a factor, as is the % of water in initial starter.  So without a lot more precision, I think it is not wise to conclude at this time that water used is only factor. But the type of water used in starter is something I am going consider when planning the timing of dough in future. And as time permits, I am going try more of these side by side experiments but other than timing and satisfying intellectual curiosity , I don't know the usefulness of confirming or disproving my anecdotal observation.

[Bill/CDMX]

The amount of starter was not by weight but by volume

Of all the ingredients, the starter is the most prone to volume variability since it contains both liquid and gas components and can also stick to the measuring cup. Furthermore, the smaller the amount of starter, the greater this variability. This may be a much bigger factor than any differences among brands of water.     

[crawsdaddy]

Good observation. Also, I think Bill's initial comment about the PH is right on target and probably the difference in the waters. The Evian bottle states that it is 7.2 neutral PH. I spent a couple of hours on the internet looking a various web sites and forums related to sourdough starters and I discovered what Bill obviously already knows about the ph levels. I think this is a fair summary of the information on those sites. 1) starter benefits from water with mineral content 2) avoid chlorine in the water  and 3) that PH between 5.0 and 5.5 was an optimum environment for starter. Obviously there was a lot of debate and comment on the forum sites about these items and people stating they had success with chlorinated water, PH's approaching 7 and water with low mineral content but I think the consensus was as summarized previously. In planning to do a test of the effect of water on the growth rate of my starter, I am going to add a spring water to the group, test the PH levels of the various waters and do a much better job of eliminating as many variables as possible. When I get this done I will post the results here but it may be some time before I get it done.

[Bill/CDMX]

Which starter? Captured, bought?

Once you are you able to accurately measure (and manipulate) pH, you will find that different starter cultures can have have very different responses to pH in multi-day fermentation. There are some people, many without direct experience in long-term management of multiple cultures, who seriously claim that all cultures devolve into the same one. Bottom line is that you have to do the work (or rather, the fun!) with extensive experimentation to learn how your particular starter responds.

Measuring pH with semi-solids can be tricky. Not sure swimming pool test kits can be used - never tried.
     

[crawsdaddy]

Which starter? Captured, bought?

Once you are you able to accurately measure (and manipulate) pH, you will find that different starter cultures can have have very different responses to pH in multi-day fermentation. There are some people, many without direct experience in long-term management of multiple cultures, who seriously claim that all cultures devolve into the same one. Bottom line is that you have to do the work (or rather, the fun!) with extensive experimentation to learn how your particular starter responds.

Measuring pH with semi-solids can be tricky. Not sure swimming pool test kits can be used - never tried.
     

Ischia from sourdough.com Culture is about 5 years old. I like what in the jar and think debates I have seen about what may or may not be in jar are interesting but not relevant to me. The Ph I am referring to is that of the various waters, not the cultures---there is a limit to my curiosity. I think it will be fun (or maddening) to experiment but with this stuff but only to a certain point. Anecdotal observations and controlling a many inputs as I can easily do will suffice for me. Incidentally , I have both bottles fed and growing for making dough for weekend; the one using the purified water is once again clearly growing faster  than the other.

[Bill/CDMX]

The Ph I am referring to is that of the various waters, not the cultures

Sorry, I misunderstood your intent. Curious to see your results.