The Fresh Loaf

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"Proper" Sourdough pH?

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davidg618's picture
davidg618

"Proper" Sourdough pH?

I've search this site, and other baking related sites, top to bottom and have yet to find a number, e.g., 3.6, or 4.2, or even a range of values of "correct" pH for mature sourdough starter. All I've found is imprecise (and a few ambiguous) references to "low" pH. That's as about precise as the three blind men examining an elephant. I've been brewing beer and making wine for years, and routinely check pH with a meter that reports a number. Simple.


Can anyone tell me the "proper range" of pH in a mature sourdough starter?


Please, don't tell me about starter variability. I know that already. All I'm asking for is a range of numbers with single decimal precision.


David G.

xaipete's picture
xaipete

My understanding from WGB is that is should be between 3.5 and 4. I bought some pH paper but I could never get my starter to register anything on the strips. I think the only way to get a really accurate read is to buy a pH meter. They cost about $100. That's a lot of money to spend just because I'm curious. If I had some other use for the meter I might consider it, but for now I'm trying not to think about it.


--Pamela

davidg618's picture
davidg618

Not for the first time (I visit your blog frequently) your clarity, and "to the point" responses have been very helpful. I guessed, from experience with other fermentables, the range was between 3.5 and 5.0. Your reply to my query gives me confidence in my guess. I own a pH meter that has served me well for more than a decade. Thank you.


David G.

xaipete's picture
xaipete

I wish I knew someone who lived around me that had a pH monitor.


--Pamela

davidg618's picture
davidg618

I'm not new to bread baking, but I am new to bread baking websites. Please, what is WGB?


Thank you,


David G.

flournwater's picture
flournwater

Peter Reinharts  -  Whole Grain Breads

proth5's picture
proth5

I measured mine  and it is 3.5


I've measured some other well cared for soughdoughs and the pH is 3.5


So I'll add another voice to the 3.5 or so pH...

Janknitz's picture
Janknitz

if we could collect data from a group of well-developed starters and get some good hard numbers?

It's too bad simple ph paper doesn't work. Then we could set parameters (i.e. hydration level, point in the metabolic cycle, even type of flour) and have a large group measure ph and compile the data.

It might yeild some interesting results.

davidg618's picture
davidg618

that's just the first of questions. What I'm trying to understand is how best to develop the "right" balance between bacterial byproducts and yeast byproducts. Bacteria contribute mostly flavor; yeast contributes mostly CO2. Yes, I know bacteria also emits gas, and yeast also effects flavor, but I stand by my arguement.


I have a six month old KA sourdough starter I've been maintaining at 100% hydration, and a very new--less than a month old--starter, alledgedly containing San Francisco bacteria and yeast. I maintain the latter in two hydration states: 200% and 65%. The very liquid SF starter provides excellent  1st and 2nd proofs in near record time, and excellent oven spring. However, its sourness is nearly undectable. The same strain, maintained at 65% hydration, is a noticeably lower performer in proofing and oven spring, and doesn't exhibit a discerable difference in flavor. Admitedly, the lack of sour flavor may be due to the starter's youth.


The KA starter has a distinct sour flavor, wonderful on the pallete, but is disappointing in proof times, and oven spring is virtually absent.


I've experimented with varying proof times, retarding (refrigerating) up to 21 hour) but the final results--for all three seed starters--don't change appreciably. I've done formula with starter freshly fed from the crock, starters I built, tripling their weight each time over three feedings with the same non-varying results.


What I'm trying to achieve is the well sprung, near lip-puckering sour loaves, reminiscent of the SF sourdough I bought when I lived in Monterey, and subsequently when work took me frequently to Bagdad by the Bay. 


I'm open to trying anything short of offering my first borne (You wouldn't want him; he's 54, bearded, and opinionated.). My science training tells me "Look to the science", the artisan in me says, "Ignore him!". I'm trying to find that balance too.


I will continue my trial and error, scientific and artisanal, experiments, but if there is anyone out there with suggestions I'll listen--and likely try--anything that sounds rational and reasonable.


Like my New Age friends say, "The journey is what's important, not the goal."


David G.


 


 

dghdctr's picture
dghdctr

Hello David,


I would second Pamela's reference to 3.5 to 4.0, but I have no empirical evidence to support that position.  It's just an opinion, and it reflects what I've experienced.


I first read that figure in an article by Monica Spiller, who has contributed in the past to the Bread Baker's Guild newsletter.   I think she used the 3.5 figure to describe a starter just before it was fed, and the 4.0 range to approximate the pH of one right after feeding. She's a scientist like you, I believe, who loves to bake.  I'm not sure if those figures corresponded to the starter feeding I described, but they're close, at least.


  She runs a company that offers some dried "barm" products, malted wheat flour to feed them, and informative pamphlets that detail her observations and recommendations for keeping the "barm" (British word for levain or sourdough) in good shape.  Her personal focus is on whole wheat and other whole grain breads, but the maintenance principles and desirable pH are the same with white breads, in my experience.


She loves to chat about this stuff, so you might e-mail her at barmbaker@aol.com ( I hope that's still current).  Her website is http://www.sustainablegrains.org/.


--Dan DiMuzio

AllenCohn's picture
AllenCohn

"Nature of the San Francisco Sour Dough French Bread Process" in The Bakers Digest, April 1970 lists pHs in that range. I found a copy of the article on the Yahoo Group for www.BBGA.org.


Allen
home baker
San Francisco

xaipete's picture
xaipete

Thanks, Dan, for the link to sustainable grains. The information on Barm Bread is really useful, esp. the information on how to add sprouted wheat to bread. It is a great link.


--Pamela

davidg618's picture
davidg618

Dan,


I purchased your book, and Emily Buehler"s "bread science". I'm delighted with both.


In an earlier forum exchange you pointed me in the direction of chapters 3 and 10 of "Bread Baking, an artisan's perspective", and asked me for feedback. I didn't find any new information in Chapter 3, personally, so I can only comment on its clarity: its excellent!


Chapter 10, on the other hand, is full of new information for me, directly and indirectly. Furthermore, I was pleased to see, despite the book's overall theme being directed at the commercial artisan, that you includied formulae scaled for the 5-quart mixer. Speaking for myself (and I suspect other amateur bakers) I found that choice a boon.


Other than chapters 3 and 10, at this time I've only rapidly read the other chapters--that's more than a scan, less than full comprehension. Nonetheless, both yours and Dr. Buehler's books have helped my dissect bread baking, from the amateur's point-of-view, into two categories: what an amateur can control, entirely or partially; and what an amateur can't control readily. I certainly haven't found all the answers, and those I think I have found aren't yet chiseled in stone.What i'm focusing on at the moment is balanced starter developement (including sourdough, polishes, and sponges), hydration%, and techniques. These, in my opinion (subject to change) are things the amateur baker has some control over.


I mentioned, in our earlier electronic conversation, I've been playing with spreadsheets to help me formulate. I've developed two you, or anyone else reading this, might find interesting. The first of these help the artisan baker choose the final batch size and hydration, and still allows manipulation of all the ingredients; i.e., the flours, fluids, and additives. I've written this in two versions: one that works in pounds and ounces, and converts to grams; and a sister spreadsheet that does exactly the same things, but works in grams, and converts to pounds and ounces. I thought these two would be helpful, not only when creating a unique formula, but also when converting cookbook recipes to starter based recipes.


The second one helps build sourdough starters. Beginning with any seed starter hydration%, and a baker's decision of how much of the final dough begins as starter, it calculates how much seed starter is needed, calculates how much flour and water to add over three builds, spaced approximately at four hour intervals (room temp.), finishing with the desired starter weight and the same hydration as the formulae the starters being built for. The program is conditioned to triple the starter weight each built. This allows a very small amount of seed starter be required. As an example I just finished three, 350 gram, SD ciabatta loaves, whose formula called for 250 gm. of starter at 73% hydration, The seed starter (200%) requred: 10 gm.


The spreadsheets were developed in Microsoft Excel (.xls extension). If you, or anyone else, is interested send me an email--davidg618@aol.com--and I'll send them to you.


Thanks again, Dan, for your guidance.


David G.


 


 

dghdctr's picture
dghdctr

I'd be very interested in seeing the spreadsheets, David, and I think there are a number of others who'd be interested here as well.  I'll e-mail you.


I was gratified that you found Chapter 3 readable.  Believe me -- baker's math is the one thing about my bread classes that scared the heck out of students.  You and I both know that it only uses concepts from 8th grade pre-algebra, but I think success rested on getting my students to see just what those weights in a pre-ferment represented, where they came from, how that affected the final dough and so on.  Once you know where the weights and percentages come from, the math is fairly easy.


I only directed you to Chapter 10 (and I hope the "Advanced" Baker's P on p181) to see if you thought the mathematical relationships were clear and understandable.  The real subject of Chapter 10 is using key concepts from preceding chapters to create one's own balanced formula.  If you don't have good familiarity with those concepts, the numbers assigned to weights and why I chose them might not make as much sense right now.


You can bake your way through the book with the chapter experiments or by using the formulas in back, but I do suggest mastering one formula at a time -- completely to your satisfaction -- before starting on entirely new concepts.  The learning curve may seem less entertaining that way, but the repetition will drive home the book's concepts much faster, and one mastered concept leads more easily to another.


I'm going to get Ms. Buehler's book myself -- I just haven't gotten around to ordering it.  I do think that a better understanding of the science behind baking (including the mathematical relationships) helps immeasurably in achieving artisanship.  There's another baking science book worth checking out that I know about.  It's Paula Figoni's "How Baking Works," in its 2nd edition.  She writes clearly and logically.  She's a food scientist and professor at Johnson & Wales.


Thanks again for the feedback,


--Dan DiMuzio

davidg618's picture
davidg618

Dan,


I feel I may have let you down, not being more specific about my reading (and rereading) of Chapter 10, and my subsequent reading your advanced comments on preferments, and their overall influence, and component contributions to final formulae, but more importantly flavor, crust, and crumb..


In a phrase, "I got it." I hope every other reader"gets it." I was trained, and worked as a "system engineer". When asked what that meant, I would analogize my job as, reading from a Chinese restaurant menu, being able to select this and that and the other from column A, and so forth and so on from column B, and creating a meal fit for the last emperor of China. I find bread baking akin, and amature bread baking especially, specifically because the amature doesn't usually have either the breadth of tools or the equivalent range of choices the professional baker has. On the other hand, the amature has a freedom to experiment, and the werewithal to spend time and resources generally denied the professional.


I'm approaching bread-baking as a system, a process, that encompasses choices of time spent, procedures used (techniques), and physical reasources incorporated, e.g., flour, water, salt and other possible components. Each--time, manipulations, and parts--contribute to the final product, individually and in combinations. You make that clear, especially in Chapter 10.. I might have called Chapter 10 "A Grand Summary" rather than merely Creating Dough Formulas. Moreover, I think the chapter speaks clearly as much to the amature artisan as it does to the professional. Yes, there are the ocassional reminders of "cost" in time spent and resources exhausted, but those comment are in the minority.


From a different point-of-view, I felt a bit over-qualified to comment on your explanations of baker's math and baker's formula.. Your explanations and examples are crystal clear to me, have no errors nor ambiguites; but I'm at home with such information. Nonetheless, the chapter helped me coelesce my own thoughts, and influenced my spreadsheet work, which, reflecting a spreadsheet's limitations, aid only in balancing resources. However, while entering numbers I find myself also choosing which techniques I'll emply, i.e., prefrement and its development, mixing, fermenting, retarding, shaping, and baking. For example, my Sourdough Starter building spreadsheet was hatched during such a moment.


Finally, Chapter 6 "Division and Shaping Loaves and Rolls" is especially useful to me. In the 1990's I started brewing beer. For two years I relied, as I often have, on books alone to guide me. It was only after I'd become a pretty good brewer, I found a local club, a group of like-interest men and women, who became my mentors, my students, and like-minded friends. Baking bread, I'm alone once again. Books, YouTube videos, and websites such as TFL and Breadcetera.com are my only mentors and teachers. (I already bake bread better than anyone in our tight-knit neigborhood.) Some of my other books, and a few videos have helped me understand bread shaping, but your book does it better than them.


Regards,


David G.

dghdctr's picture
dghdctr

Hi David,


After reading the above I'm not sure how you think you let me down, but you didn't.


I'm glad you're finding the book to be useful.  If you encounter any errors (in typing or in judgment) please let me know.  I'm trying to get an errata list together to be sent Wiley's way fairly soon.


--Dan DiMuzio