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sourdough starter impairs gluten development perhaps?

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maja z's picture
maja z

sourdough starter impairs gluten development perhaps?

I started my own sourdough starter a couple of months ago - simple organic white bread flour and water - and moved it into the fridge a couple of weeks later. It is lovely, lively and just the right level of sourness.
But I have recently started to notice something odd.
My method is to perpare a semi-stiff preferment, before mixing the final dough, i usually don't knead it much, but rather let it rise for 8-12 hours with random folding in between. The folds usualy quite clearly make the dough stronger and smoother, but recently it feels like the opposite is happening. The folds or short kneads seem to make the dough "break up" - instead of the surface becoming smooth it starts to break up, and the dough becomes more sticky each time. It feels like perhaps somehow the gluten isn't strong enough - and i'm not handling it too roughly.
I am perplexed as the first month or so, even after moving the starter to the fridge, it was working so perfectly, but now it's getting more and more frustrating.
The final bread still turns out fine - if only after a bit more effort: i've had to reduce hidration, retard it, increase proofing time, because it somehow doens't have the upmf anymore. But the final bread still tastes lovely i.e. I haven't noticed any increase in sourness or anything like that.
Any ideas? Will be greatly appreciated!
Maja.

LindyD's picture
LindyD


My method is to perpare a semi-stiff preferment, before mixing the final dough, i usually don't knead it much, but rather let it rise for 8-12 hours with random folding in between.



Are you kneading and folding the preferment?  If so, why?


If I've misunderstood, my apologies.  Please post the recipe you are using.

maja z's picture
maja z

No, no, sorry if I was unclear Lindy, the preferment is simply incorporated together and left over night. In the morning I mix the final dough, adding more flour, water and salt - this I knead slightly and then fold throughout the day.

The recipe is along the following lines:

preferment:
50 g starter
100 g flour
50 g water

final dough:
200 g preferment
500 g flour
300 g water
1 tbsp salt.

Although I tend to add the water "by feeling" to achieve the right feel, so it depends on the flour etc.

Anyway, as I said, it used to work fine, I am quite sure something has changed about the starter...
M.

LindyD's picture
LindyD

Maja, you mentioned you are refrigerating your SD culture.  Do you remove it a couple days before you plan to bake and refresh it either daily or twice a day?

Debra Wink's picture
Debra Wink


The folds usualy quite clearly make the dough stronger and smoother, but recently it feels like the opposite is happening. The folds or short kneads seem to make the dough "break up" - instead of the surface becoming smooth it starts to break up, and the dough becomes more sticky each time.



What you describe sounds like your starter has become sluggish and overly proteolytic. You may be developing the gluten okay, but it's breaking down through enzyme action, especially if you're extending fermentation times waiting for the dough to rise.


Your starter needs to be put on a more intensive feeding program until things turn around, and then you'll need to adopt a healthier maintenance routine :-)


-dw

Mike Avery's picture
Mike Avery

Hi, I'm Mike and I'm a starter abuser.  I've tried to give it up, and I try to do well, and I'm doing better than I used to, but, oh, the stories I could tell you!


 


What, this isn't starter abusers anonymous?  Oh, well, forget that stiff then.


 


In any case, I've had a few starters become proteolytic.  They all had a pronounced acetone smell to them,  (Like cheap fingernail polish remover, for those who haven't smelled acetone.)  And I don't think I've ever been able to fully rehabilitate one of those starters.  With intensive feeding, they start acting right, but if you miss a few feedings, WHAMMO - the proteolytic nature returns.  Didier Rosada, if memory serves, suggested there was no point in trying to revive such a starter.  Just start a new starter and go and sin no more.


Not being a micro-bioligist, I don't KNOW what's happening on the micro-biological level.  However, my speculations are along these lines... some bacteria can digest proteins.  Most of our starters are natural starters, started by whatever was on the flour and whatever craweled into the vat and survived.  The yeast and bacteria we want are normally dominant by orders of magnitude.  So, when you forget to feed the starter for weeks on end, do critters that were in the minority take over because conditions are more favorable to them?  Or do some of the bacteria we want suddenly discover that they can digest protein also?


When the baker wakes up to the problem and starts feeding the starter, either the critters we want take over again, or the bacteria stop performing that cute trick with the protein.


However, it seems to take less time for the bac bacteria to take over again, or for the good bacteria to re-learn that bad trick in the future.


 


I haven't been baking as often as I used to since I moved and got a day job with 2 hours of commute time every day.  So, my starter begain doing this again.  I'd been meaning to try Dr. Wood's washing technique.  I don't know if my starter has been fully rehabilitated, but it is behaving better, at least for now.


 


Any ideas Debra?


 


Thanks,


Mike

Debra Wink's picture
Debra Wink

Hi Mike,


Since we're confessing, I'm a starter abuser too---that's how I have accumulated "experience" in reviving them ;-)



my speculations are along these lines... some bacteria can digest proteins...  when you forget to feed the starter for weeks on end, do critters that were in the minority take over because conditions are more favorable to them?  Or do some of the bacteria we want suddenly discover that they can digest protein also?...  When the baker wakes up to the problem and starts feeding the starter, either the critters we want take over again, or the bacteria stop performing that cute trick with the protein.



Both scenarios are possible, theoretically speaking, so I couldn't say with certainty that it's only one thing or the other. Underfed starters can get very acidic, and pH may be the biggest determiner as to which species of LAB lands on top. The most desireable are also the most sensitive to low pH, and so they can easily be knocked out of the top position by something less desirable that is more acid-tolerant. But I don't think this is as likely to happen, or at least not as quickly, in a refrigerated starter as one neglected on the counter. Also, when LAB are starved, they turn to alternate metabolic pathways that result in less tasty and fragrant by-products.


Lactobacilli have complex dietary protein needs, which they fill from amino acids in the flour. They start by consuming the free amino acids, and when supply runs short, some can produce proteases to extract amino acids from the proteins. If I understand right, they manufacture proteases only on an as-needed basis. But enzymes don't quit when bacteria do. They can continue doing their damage as long as they are present. The organisms in a well-fed starter have less, or no need to make these enzymes, but it will take at least a few refreshments to flush them out and reduce their effect. The washing technique may be a good idea here, since it flushes out a lot of undesireable substances all at once through massive dilution, but it's more of a shock to the organisms, and I'm not sure such drastic measures are really necessary.


I can only speak from my own experience, but I have had good luck reviving my starters and turning them around with intensive feeding (i.e., each time they peak or soon thereafter). It generally takes 3-7 days, and so the results aren't immediate, but I find it quicker to fix the one I have than to start a new one and get it where I want it. Even with pineapple juice, it takes 3-4 days to sprout yeast (at room temp), and then probably another couple weeks to establish a good sanfranciscensis population (or whatever it is that makes it get even more fragrant and robust at that point). I am open to the possibility that others may have a different outcome, but my general impression is that many people don't give their starters enough time to make a complete transformation. And of course, if you go back to doing what you did before, the starter will do the same..... just like eating and weight, unfortunately.


I think what it boils down to, is that there isn't a one-size-fits-all solution, but learning to recognize what the starter needs and responding to that is key. I know that you already know this well, but it bears repeating for others reading along :-)


Debbie


It's never that simple with living things...

maja z's picture
maja z

Thanks guys, that sounds about right - my starter becoming proteolytic...
I was hoping the fridge regiment would let me relax a bit from the original twice a day feeding routine! Seriously, if I leave it outside, it is so lively, i have to keep feeding it twice a day, and with all the discarded starter (I will bake twice a week) it only made sense to slow it down.
In the fridge I have it for about three days without feeding, then I take it out in the morning, feed it, feed it again in the evening, leave it to recover for 2, 3 hours, then put half of it back in the fridge and half into my preferment.
That's the plan anyway, sometimes I skip the morning part and just do the second part i.e. feed it from the fridge and leave it out a couple of hours to wake up before using it in the preferment.
So I guess more regular feedings are in order, and am I then right in thinking I should leave it out for a couple of hours before puting it back in the fridge?
Thanks guys!!!
m.

edit:
How about this: salt in the starter? Here's a quote from "The Taste of Bread" by Calvel et al., page 89 (on google books) :

"Salt is added to protect the dough against the action of proteolytic action that might possibly weaken the gluten during the very earliest stages of dough fermentation. This proteolytic effect might otherwise damage the dough by softening it excessively, since this first fermentation stage may last for more than 20 hours. For this same reason, salt also fulfills and important role in the renewal or feeding of cultures that are ultimately to be used in the building of a naturally fermented sponge or levain."

How about that? Has anyone heard of or tried adding a sprinkle of salt to their sourdough starter?
M.
Crider's picture
Crider

Since you say the yeast in your starter is so active with twice-daily feedings (makes sense to me), I think it is the folding you're doing during the bulk fermentation which is causing your dough to breakdown. I say this because I've been goofing around with prolonged bulk ferment, with as long as a 24-hour ferment. I'm using about 1/3 cup of starter right out of the refrigerator. The difference is that I'm doing my kneading or folding at the beginning and am then leaving the dough undisturbed for most of the ferment. Doing this technique has been giving me super sour, but I've also experienced gluten breakdowns by bulk fermenting for too long during our warmer weather.


Each time you're folding the dough, you're doing an Armageddon on the yeast/bacteria colonies. They all get moved around quite a bit. Their local environment is changed. This is like doing a mini punch-down of the dough. While you're moving more sugars to your yeast, the bacteria need to reestablish their colonies near the yeast. So, based on your description of your starter and your maintenance schedule, I think the starter is just fine.


There's an interesting silent 1931 documentary called In the Dough from the Prelinger Archives where they compare flours by rising and punching them down four times. May or may not have anything to do with your dough issues, but does show dough getting exhausted in a very old-fashioned way.


http://www.archive.org/details/in_the_dough_2


 

Debra Wink's picture
Debra Wink

To save on discards, you can scale your storage leaven back to a very small amount. Whatever you're comfortable with or feel you need to have on hand. I keep just 2 oz in an 8-oz canning jar---the short wide-mouth for firm starter and the taller jelly jar for liquid. I like canning jars because the two-piece lids are designed to vent pressure, even when "finger-tight." That's my tip for the day :-)


When I'm refrigerating for preservation, I feed my starter and put it directly into the fridge. Preferably after a feeding cycle or two at room temp first. I don't think it needs to sit out a few hours, unless you want a starter that is ready to use from the refrigerator for bread baking in the next couple days (as for formulas using "barm" in BBA).


I add salt to whole wheat starter sometimes in the summer. LAB are more sensitive to it than yeast, and so I use it to slow them down. It seems to get less sour, and rises better for me. I don't know if it has a direct effect on the enzymes or not, but slowing LAB and reducing their acids will reduce the proteolytic effect.


-dw

Mike Avery's picture
Mike Avery

Debra sagely commented:



When I'm refrigerating for preservation, I feed my starter and put it directly into the fridge. Preferably after a feeding cycle or two at room temp first. I don't think it needs to sit out a few hours,



 


I'd go one step further.  Dr. Sugihara looked at the survival of yeast and bacteria in frozen starters.  He found that fresher starters had less die-off than mature ones.  I haven't seen any studies with refrigerated starters, but suspect the same holds true of refrigerated starters.


 


So, I feed my starter until it's happy, lively and smeilling good.  Then I feed it one more time and put it into the fridge at once.  My starters have been reviving MUCH more quickly since I started doing this, and lasting longer as well.  (Ooops.. that gets us back to the starter abuser thing, doesn't it?)


 


Mike


 

charbono's picture
charbono

In addition to Prof Calvel, Monica Spiller's barmbread recipe at http://sustainablegrains.org/index.html has salt in the starter.  She does it for a different reason than Calvel -- to select microbes.