Author Topic: do all sourdough starter cultures become the same?  (Read 22251 times)

0 Members and 1 Guest are viewing this topic.

Offline JimmyG

  • Registered User
  • Posts: 477
Re: do all sourdough starter cultures become the same?
« Reply #80 on: March 25, 2012, 01:32:14 PM »
Grimaldi,
Glad to hear you were able to cultivate a good sourdough culture from your local grapes. I tried this method twice with grapes grown locally in my area. The flora I cultivated from these grapes was so active that it turned my dough balls to sludge within 12 hours. Mind you, I was adding less than 3% starter to my dough recipe and the dough was refrigerated overnight at 45F. In both cases, I had to dump these starters. However, my current starter was cultivated from the local apples and it works great.  I guess it demonstrates that there is quite a bit of diversity in starter activity and preformance depending on where you live and what methods you use to cultivate your starter.  

Regarding flora takeover, from what I have read in the scientific literature and in my own personal experience, this is not likely to happen under most circumstances for home bakers. The major contributors for a takeover from what I have read are at temps above 30C (86F) and prolonged starvation near or above those temps. To some degree this makes good biological sense. The rate of bacterial fermentation begins to exceed the rate reproduction at those temp. Once the main source of food is greatly diminished, it's every bacteria and yeast for itself. Less hardy species under those conditions will die off and better adapted species will eventually take their place. Additionally, the degree to which this may happen will depend upon what species are in your starter. If your starter flora is principally composed of hardy microbes, its less likely to be taken over under extreme conditions. In any case, the majority of home bakers are unlikely to maintain +80F conditions and not feed their starters for weeks on end at these temps. Therefore, it is very unlikely that any take over is will ever take place under normal circumstances.
« Last Edit: March 25, 2012, 01:33:45 PM by JimmyG »
Discovery consists of seeing what everybody has seen and thinking what nobody has thought.


cornicione54

  • Guest
Re: do all sourdough starter cultures become the same?
« Reply #81 on: March 25, 2012, 01:38:10 PM »
Chau - it might have been because of not feeding it enough while at room temps. I didn't have a feeding schedule but fed it when ever I thought about it (maybe every 3 or 4 days). My past experience has been rapidly multiplying the starter at room temps - not just letting it just sit out.

I'm back to keeping the starter refrigerated and sealed - and only keeping it at room temps when multiplying.

I got into using a starter without much research about the how's and why's. I just took a bunch of the wild grapes from a vine 50 feet from the house along a fence line and added water and flour - it became active overnight. It is now 2 years old.

Thanks for your reply's.  

Nice!

Grapes (esp. grapes straight from the vine) tend to attract "wild" yeast on their surface (that's how spontaneous fermentation of wine occurs). Such yeast have different metabolic characteristics to the ones typically found in (solely) flour/water sourdough starters as they don't seem to require lactobacilli to propagate in significant number.

In fact you don't need flour at all to activate these yeast - just soak grapes (or raisins as I have tried or indeed many other fruit/veg) in water and leave in a warmish place. When they start bubbling and rising to the surface you can strain out the liquid for use as a leavening agent for bread or pizza dough.  The initial results will likely not be as sour as your average sourdough culture but if  you start feeding  flour and water then lactobacilli should start to populate alongside the yeast in due course.

additional:
@ Chau - fwiw the scenario above is similar to what happens (albeit in reverse) when you add commercial yeast to a starter culture. The two can coexist although there's more of a competition for maltose. Acid (esp. acetic) as a product of Lb fermentation may keep the commercial yeast "in check" somewhat. The flavour profile may not necessarily be affected too much except for overall less acidity which seems consistent with the results you observed.
« Last Edit: March 25, 2012, 02:10:14 PM by cornicione54 »

Offline Jackie Tran

  • Registered User
  • Posts: 6977
  • Location: Albuquerque NM
Re: do all sourdough starter cultures become the same?
« Reply #82 on: March 25, 2012, 02:13:39 PM »
Thank you Jimmy G and Cornice.  This is a lot of good information that is coming out.  You guys are really smart to understand the science behind this stuff.   As a follow up to member Bakeshake and PM's exchanged, I am going to do a CY starter test.  I will maintain one in the fridge to be fed every 2-3 days as per my usual routine and another one at room temps (~75F) which I will feed 1-2x a day.   I want to see if the room temp one will develop any additional flavors over 2-3 weeks time.  I have not done a temperature comparison like this before so this is very interesting and exciting to me.  

If we discover that the temperature difference does indeed lead to a change in SD cultures or takeover, this will be very good information for the forum and the SD community.  Member bakeshake has agreed to do the same test with CY and another SD starter of his choosing.  Anyone else who is interested in doing the same test and post their results is welcome to.  It will be much appreciated.  The more info we can get to help clear up this mystery the better.  

Chau
« Last Edit: March 25, 2012, 02:59:31 PM by Jackie Tran »

Offline JimmyG

  • Registered User
  • Posts: 477
Re: do all sourdough starter cultures become the same?
« Reply #83 on: March 25, 2012, 02:51:39 PM »
Chau,
I may get into the fun of this experiment as well. The only thing differently I may do differently is, after the two week period I may starve both cultures for a week and then refresh for two days or split the starters in two, so four starters total, and starve two and maintain the other two as before. I am curious about the starving aspect at room temp and if it also influences flavor.

Discovery consists of seeing what everybody has seen and thinking what nobody has thought.

Offline Jackie Tran

  • Registered User
  • Posts: 6977
  • Location: Albuquerque NM
Re: do all sourdough starter cultures become the same?
« Reply #84 on: March 25, 2012, 03:00:05 PM »
Chau,
I may get into the fun of this experiment as well. The only thing differently I may do differently is, after the two week period I may starve both cultures for a week and then refresh for two days or split the starters in two, so four starters total, and starve two and maintain the other two as before. I am curious about the starving aspect at room temp and if it also influences flavor.



That is a good idea Jimmy.  Please keep us updated if you decide to do the test. 

Offline dmcavanagh

  • Registered User
  • Posts: 1912
  • Location: Glenmont, NY
Re: do all sourdough starter cultures become the same?
« Reply #85 on: March 25, 2012, 03:16:42 PM »
Since I have a captive audience on this thread, I have another question for discussion. When you guys keep a starter idol and under refridgeration of a long period of time, do you pour off the hooch, or do you stir it back into your culture. Why, or why not? I generally pour off at least some if not all, just wanted to get some other opinions.

Offline Jackie Tran

  • Registered User
  • Posts: 6977
  • Location: Albuquerque NM
Re: do all sourdough starter cultures become the same?
« Reply #86 on: March 25, 2012, 03:24:25 PM »
Since I have a captive audience on this thread, I have another question for discussion. When you guys keep a starter idol and under refridgeration of a long period of time, do you pour off the hooch, or do you stir it back into your culture. Why, or why not? I generally pour off at least some if not all, just wanted to get some other opinions.

Dave, I have only read posts whereby it is recommended to stir it back in.  I personally do not as it makes no sense to me.  I dump ALL of it along with most of the old starter.  By the time a starter gives off hooch, it is way beyond useable filled with tons of acid and metabolic by products, which IMO affect crumb textures.  I retain only a small fraction of the starter and refeed.  If a starter has gotten to this point, it may require multiple feedings to get it back to it's peak strength.

Offline dmcavanagh

  • Registered User
  • Posts: 1912
  • Location: Glenmont, NY
Re: do all sourdough starter cultures become the same?
« Reply #87 on: March 25, 2012, 03:33:34 PM »
Tran Man

That's how I feel, I can't see why anyone would want that hooch stirred back in, but like you said, I have read that many do that. I have some starters in a spare fridge in the basement, it's probably time for me to tend to them or ditch them.

Online TXCraig1

  • Registered User
  • Posts: 12457
  • Location: Houston, TX
Re: do all sourdough starter cultures become the same?
« Reply #88 on: March 25, 2012, 04:32:41 PM »
Why?  Because its impossible?  Or because its unlikely? 
Neither, itís absurd because it has strayed so far from the original question posed. Why not just pour bleach in your culture? That would certainly open the door for a new culture to take over. The question was ďdo all sourdough starters become the same?Ē not can you force them to all become the same, or if you mistreat your starter to the point of death will it change.

Quote
And furthermore, how would you explain all these different observations out there?  Would you simply say that everyone who experiences their starter's uniqueness withering away over time with successive feeding cycles is a flat out liar?  That's too easy.
You answer your own question below. 

Quote
A week is nothing. Try an entire summer in an unairconditioned place because you spend the summers somewhere else in another state.  I'm describing myself there.

Why, you donít have a fridge?

Quote
And yes, I've had mold grow in starters.  And I've resurrected starters with mold in them.  Mold does not necessarily mean all hope is lost.  Just dig down past the mold, grab a tiny sample, put it in a new jar, add some flour and water and within the next two weeks or so of intensive care you're back at full froth.

More power to you.

Quote
I do not believe that the healthy yeast cells present within the flour need to be at high concentrations to contaminate a weak colony, which is by definition an unstable colony. 
A weak colony or a dead colony? Assuming weak, the invading yeast introduced with the flour is also going to be weak Ė probably a lot weaker Ė and at much lower concentrations. Iím still looking for your explanation as to how it takes ďa month or two to [grow a new starter] realistically.  Maybe even longer,Ē but when the same flour is added to an existing culture, suddenly these yeasts are ready to take over?

Itís just not going to happen, by the time they reach any sort of activity, the existing colony will have consumed the food and the space. Unless they multiply faster than the existing colony, even when the get healthy, the will not be able to make up ground.

Quote
You don't need a complete takeover to change characteristics.  You simply need contamination to do that.
Iíll love hearing how you support this. The invading culture will be at concentrations thousands Ė maybe 100ís of thousands Ė of times lower than the existing colony, and you think you will notice the difference?


Quote
With due respect to you, you should read the thread a little more thoroughly before replying.  I don't feel like its that long.

I read what you wrote. Problem is you addressed something other that the question at hand. And, did you really feel the need to try to be uppity and disrespectful?

Quote
I've stated, in my very *first* post AAMOF, that folks should not have a problem maintaining purchased starters so long as they take care of them properly.  I've also stated, more than once, that under proper circumstances there should be no real issue with native microorganisms taking over a sourdough culture.  I've stated that, so you should not be attributing alternate beliefs to me by this point.
I didnít. I only addressed your points that went way beyond this.

Quote
However, I have also stated that there is some truth to the idea that starters are hardly 'bulletproof' things.  'Indestructible' is not a common description for a sourdough starter.  This thread would, in fact, be the first time I've ever even seen that implied.  Here we have folks literally scoffing, implying that any negative experiences reported with sourdough sustainability are utterly unbelievable!! 
You read too much between the lines. I donít see anyone who disagrees that you can intentionally destroy a culture and repopulate it with another, but that was hardly the question at hand.

Quote
Based on what I've seen, sourdough cultures are instead most often described as 'finicky, temperamental, inconsistent, and not worth the trouble' compared to plain yeast.

You have not heard any of that from me. Quite the opposite in fact. 1000+ posts will back that up.

Quote
In other words, it ain't exactly uncommon to have a starter destroyed and to have to replace it, or reorder another one.  Apparently, though, nobody here has ever heard of that.
Itís never been a problem for me. I canít remember anyone else ever complaining about it save an accident like the maid flushing it down the drain thinking it was garbage.

Quote
Lastly, I have also stated in post #19 that changing food sources can mean changing a lot.  It really can turn out to be a pretty big deal.  You can change an entire culture based on what you feed that culture over a sustained period of time.  Switching food sources means switching certain enzyme concentrations, certain sugar concentrations, certain impurity concentrations, etc, etc in the actual food source.  This means that for a given strain of microorganism different metabolic pathways now become preferred, which means that the same byproducts being produced by these microorganisms are now being produced at different relative concentrations. 

This alone can give the *impression* of the starter changing over time with successive feedings, even though the microorganisms actually present have not changed that much at all in terms of their relative concentrations.
My point exactly. See, you knew the answer to your own question above all along. Turns out it was easy after all.


Pizza is not bread.

Online TXCraig1

  • Registered User
  • Posts: 12457
  • Location: Houston, TX
Re: do all sourdough starter cultures become the same?
« Reply #89 on: March 25, 2012, 04:34:58 PM »
I don't think its strange at all.  Its a sourdough.  Inconsistency is the *norm* for sourdough, not the exception. 
Maybe for you.


Quote
This is a big reason why the vast majority of commercial pizzerias don't use it.  Including those in Naples.
Iíve never run my business to steer away from doing the right thing because it is difficult. Rather we do what is best. I donít look at pizza any differently. Nothing in life is consistent, but with effort, you can narrow the uncertainty to where it is manageable Ė IFF you are willing to put in the effort.

Quote
Varasano can hardly predict how many customers he's going to get on a given day anyhow, so how would he ever be perfectly consistent?  He may have a big batch of dough left over from the day before on one occasion and then on the next occasion he may have nothing left from the previous day at all.
What does this have to do with delivering a consistent product?


Pizza is not bread.


Online TXCraig1

  • Registered User
  • Posts: 12457
  • Location: Houston, TX
Re: do all sourdough starter cultures become the same?
« Reply #90 on: March 25, 2012, 04:35:41 PM »
I think this all says it isn't the yeast we should be so worried about changing.  It's the bacterial portion of the colony that we should be more focused on.
I think this is even less likely than the idea of a complete takeover of both yeast and bacteria. Sourdough culture is a symbiotic relationship between specific species/strains of specific yeast and bacteria. Doesnít mutualism work as a natural defense against exactly what you are suggesting?


Pizza is not bread.

Offline David Deas

  • Registered User
  • Posts: 346
Re: do all sourdough starter cultures become the same?
« Reply #91 on: March 25, 2012, 06:00:51 PM »
I think this is even less likely than the idea of a complete takeover of both yeast and bacteria. Sourdough culture is a symbiotic relationship between specific species/strains of specific yeast and bacteria. Doesnít mutualism work as a natural defense against exactly what you are suggesting?




I dont know what to make of this here.  Both yeast and bacteria can exist without one another, and frequently do.  You could argue that the relationship is synergistic, but its unbelievable that you are actually claiming that either cannot exist without the other or that specific strains need specific strains.  You do realize that yeast can be isolated, right?  Just about any yeast strain you can dream up is available for purchase.  Even commercial yeast was once natural.  And if you want the bacteria dead in your starter simply add some vodka to about 5% alcohol and you'll do exactly that.
« Last Edit: March 25, 2012, 06:06:49 PM by David Deas »

Offline dmcavanagh

  • Registered User
  • Posts: 1912
  • Location: Glenmont, NY
Re: do all sourdough starter cultures become the same?
« Reply #92 on: March 25, 2012, 06:15:27 PM »
I usually don't like to get into discussions about sourdough, too many conflicting opinions and information or more likely misinformation. 


Like I said, sourdough is a topic best left out of friendly conversation! :-X


Offline David Deas

  • Registered User
  • Posts: 346
Re: do all sourdough starter cultures become the same?
« Reply #93 on: March 25, 2012, 06:33:01 PM »
Maybe for you.

Iíve never run my business to steer away from doing the right thing because it is difficult. Rather we do what is best. I donít look at pizza any differently. Nothing in life is consistent, but with effort, you can narrow the uncertainty to where it is manageable Ė IFF you are willing to put in the effort.
What does this have to do with delivering a consistent product?




So after being called "uppity", I get a short lecture about how the right way to make pizza is with a sourdough.  About how the best thing to do is use a sourdough.  I guess all you lazy commercial yeast folks are making pizza wrong.  

This is in response to me pointing out the fact that most pizza makers across the globe, even the *best* ones, have switched to commercial yeast because the difficulties inherent with sourdough can make it not worth the headache.  If that's your response then I've got news for you.  What is "best" is very subjective.  Especially in a case like this.  And especially dealing with food in general.
« Last Edit: March 25, 2012, 06:40:51 PM by David Deas »

Online TXCraig1

  • Registered User
  • Posts: 12457
  • Location: Houston, TX
Re: do all sourdough starter cultures become the same?
« Reply #94 on: March 25, 2012, 07:07:52 PM »
I dont know what to make of this here.  Both yeast and bacteria can exist without one another, and frequently do.  You could argue that the relationship is synergistic, but its unbelievable that you are actually claiming that either cannot exist without the other or that specific strains need specific strains. 
Once again, you are reading things that were not written. I didnít even mention the word synergistic. I said symbiotic which is absolutely accurate. Of course the specific yeast and bacteria strains could exist without each other, but they thrive in the sourdough culture because of the mutualism.

Itís no accident that you find specific strains of S. exiguus or C. milleri and specific strains of L. sanfranciscensis together, for example. Water causes amylase enzymes to break down the starch in the flour into sucrose and maltose. L. sanfranciscensis predominantly feeds on the maltose (and often can't metabolize other sugars); S. exiguus can't metabolize the maltose, so there isn't any competition for food. While consuming the maltose, the L. sanfranciscensis releases an enzyme that breaks down maltose into two glucose molecules. L. sanfranciscensis will use one of the molecules leaving the other, boosting activity of S. exiguus. In addition to the acids produced, the L. sanfranciscensis also produce other antibiotic agents that keep other bacteria down without affecting the yeast. The specific strains that work the best together will win out thus resisting invasion by other species/strains.


Quote
You do realize that yeast can be isolated, right?  Just about any yeast strain you can dream up is available for purchase.  Even commercial yeast was once natural.
You have a firm grasp on the obvious.

Pizza is not bread.

Online TXCraig1

  • Registered User
  • Posts: 12457
  • Location: Houston, TX
Re: do all sourdough starter cultures become the same?
« Reply #95 on: March 25, 2012, 07:24:33 PM »
So after being called "uppity", I get a short lecture about how the right way to make pizza is with a sourdough.  About how the best thing to do is use a sourdough.  I guess all you lazy commercial yeast folks are making pizza wrong.

This is in response to me pointing out the fact that most pizza makers across the globe, even the *best* ones, have switched to commercial yeast because the difficulties inherent with sourdough can make it not worth the headache.  If that's your response then I've got news for you.  What is "best" is very subjective.  Especially in a case like this.  And especially dealing with food in general.

I called you ďuppityĒ because I couldnít think of a friendlier way to address your disrespect which I thought uncalled for.

Since you donít know me, I should have been clearer. I should have written ďIíve never run my business to steer away from doing the right thing because it is difficult. Rather we do what is best for us. I donít look at pizza any differently.Ē

For me, sourdough is best. I donít shy away from it because it is difficult. Iím not telling you or anyone else how to do what you do. I couldnít care less.

If you donít believe me, I challenge you to look through my posts and find even one where I explicitly said what I do is better than how someone else does it without them expressly asking for such an opinion.

I donít understand why you seem so bound and determined to put the most negative possible spin on things written?


Pizza is not bread.

Offline David Deas

  • Registered User
  • Posts: 346
Re: do all sourdough starter cultures become the same?
« Reply #96 on: March 25, 2012, 07:44:39 PM »
Once again, you are reading things that were not written. I didnít even mention the word synergistic. I said symbiotic which is absolutely accurate. Of course the specific yeast and bacteria strains could exist without each other, but they thrive in the sourdough culture because of the mutualism.

Itís no accident that you find specific strains of S. exiguus or C. milleri and specific strains of L. sanfranciscensis together, for example. Water causes amylase enzymes to break down the starch in the flour into sucrose and maltose. L. sanfranciscensis predominantly feeds on the maltose (and often can't metabolize other sugars); S. exiguus can't metabolize the maltose, so there isn't any competition for food. While consuming the maltose, the L. sanfranciscensis releases an enzyme that breaks down maltose into two glucose molecules. L. sanfranciscensis will use one of the molecules leaving the other, boosting activity of S. exiguus. In addition to the acids produced, the L. sanfranciscensis also produce other antibiotic agents that keep other bacteria down without affecting the yeast. The specific strains that work the best together will win out thus resisting invasion by other species/strains.

You have a firm grasp on the obvious.



You did not mention synergistic.  I did not say you did.  You did mention symbiotic, which itself is such a poorly defined term that I submitted "synergistic" as something concrete enough to work with.  Something that you could argue.  I thought that "synergy" was consistent with what you were saying, which was that the yeast and the bacteria thrive in the presence of one another.  Or that they do better with each other than without.  So what in the heck is the problem?

Then you go on regurgitating whatever you just Googled, which does not answer the question about whether bacterial colonies can experience changes due to treatment that impact the performance of the starter.  And what specifically those changes are.  How reversible are these changes?  

Nope.  You're still stuck talking about a takeover from the flour, which we've all admitted is unlikely for one reason or another.
« Last Edit: March 25, 2012, 07:54:04 PM by David Deas »

Offline David Deas

  • Registered User
  • Posts: 346
Re: do all sourdough starter cultures become the same?
« Reply #97 on: March 25, 2012, 08:06:47 PM »
I called you ďuppityĒ because I couldnít think of a friendlier way to address your disrespect which I thought uncalled for.

I donít understand why you seem so bound and determined to put the most negative possible spin on things written?




I don't understand why you seem to bound on pretending I've disrespected you.  You're the one who marched in here talking about what was absurd.  Is it disrespectful if I don't bend down and kiss your "right" rear end?

I gave a hypothetical scenario that I'd also admitted prior to was less likely IMO and you've been harping on that ever since.
« Last Edit: March 25, 2012, 08:09:10 PM by David Deas »

Online TXCraig1

  • Registered User
  • Posts: 12457
  • Location: Houston, TX
Re: do all sourdough starter cultures become the same?
« Reply #98 on: March 25, 2012, 08:07:24 PM »
You did not mention synergistic.  I did not say you did.  You did mention symbiotic, which itself is such a poorly defined term that I submitted "synergistic" as something concrete enough to work with.  Something that you could argue.  I thought that "synergy" was consistent with what you were saying, which was that the yeast and the bacteria thrive in the presence of one another.  Or that they do better with each other than without.  So what in the heck is the problem?

Then you go on regurgitating whatever you just Googled, which does not answer the question about whether bacterial colonies can experience changes due to treatment that impact the performance of the starter.  And what specifically those changes are.  How reversible are these changes?  

Nope.  You're still stuck talking about a takeover from the flour, which we've all admitted is unlikely for one reason or another.

Actually, I googled that a long time ago  :-D

Where else is the takeover going to come from if not from the flour?
Pizza is not bread.

Offline David Deas

  • Registered User
  • Posts: 346
Re: do all sourdough starter cultures become the same?
« Reply #99 on: March 25, 2012, 08:11:14 PM »
Actually, I googled that a long time ago  :-D

Where else is the takeover going to come from if not from the flour?

You're stil talking about a takeover, period.  I've already answered where such a "takeover" might likely come from.