The Fresh Loaf

News & Information for Amateur Bakers and Artisan Bread Enthusiasts

using IDY instead of juice to begin a sourdough starter

sallam's picture
sallam

using IDY instead of juice to begin a sourdough starter

Greetings

A sourdough starter needs only flour and water, right?
We use juice in the first 3 days to provide acidity that prevents bad bacteria from invading the starter, allowing natural yeast to develop and take over from there, correct?

If so, why not use commercial yeast instead of fruit juice? We will hit the same goal. No bacteria can come near a yeasted dough. Then, as we feed it more flour, which has natural yeast and lactobacteria, plus what it would catch from the air, eventually, the yeast and the lactobacteria from the flour and the air will take over, turing it into a sourdough starter. In either cases, both the juice and the commecrail yeast will almost cease to exist in the starter.

This is probably the same reason why long preferents give bread some sour rich taste. Preparing a poolish with a tiny amount of yeast, allowing it to ferment for a day or so, would give results close to the taste of sourdough. The poolish must have caught some natural yeast from the air and from the flour.

Did anyone try to make a starter this way?
I've started my own experiment yesterday.


Day 1:
I've mixed
2T water
2T freshly milled wheat
a very tiny pinch of instant dry yeast (less than 1/8 teaspoon)
after 12 hours, I've added another 2T water and 2T freshly milled wheat

Day 2:
I've added 2T milled wheat, no water
after 3 hours, its full of holes, almost doubled and has a lovely smell (like fresh biscuits)

jcking's picture
jcking

No bacteria can come near a yeasted dough

That assumption is incorrect.

Crider's picture
Crider

to make a sourdough culture. You can use it right away to bake. The wild yeast will eventually take over, but you need two weeks or so before the bacteria culture is fully populated. When that happens, the original yeast will die off -- to be replaced by the wild yeast.

sallam's picture
sallam

Crider, thanks for the encouraging confirmation. I can maintain it for 2 weeks, so far the results are promising.

7 hours after feeding, it colappsed, so I gave it another feed.
This time I discarded it except 1T, and mixed it with 2T milled wheat and 1T distilled water.

Mini Oven's picture
Mini Oven

and it is important to stick to a schedule.  Commercial yeast is hungry stuff at 1:1:1 (starter:water:flour) and demands food and to be fed under well under 12 hours but do not give in and feed it (unless you want to raise fast yeast like your original intention --feeding every 4 hours.)   Let it rise, collapse and stew in its own juices.  The idea is to increase the acidity of the culture to help good acid loving bacteria and acid loving yeast and encouraging them to outnumber and push out the commercial yeast sooner.   Just let the starter sit now for 24 hours and then start adding food for several days feeding every 12 hours.  (in 24°C)  Then after about 3 days, start discarding and feeding every 12 hours.  Use the discards in bread, no need to waste any of these discards for they are unlike many other wild yeast starters whose first few days of discard are better thrown into the compost pile.

sallam's picture
sallam

Let it rise, collapse and stew in its own juices.  The idea is to increase the acidity of the culture to help good acid loving bacteria and acid loving yeast and encouraging them to outnumber and push out the commercial yeast sooner.

Thanks for that advice. Makes perfect sense.. I'll start to follow it for 3 days.

Chuck's picture
Chuck

...why not use commercial yeast...

Then why bother with "wild yeast" at all???

It seems to me that the books that tell you to make a "starter" by mixing flour and water and commercial yeast a day or two ahead of time are really making what today's bakers would call a "biga".

 

... the yeast and the lactobacteria from the flour and the air will take over...

Not necessarily.  (This only happens whenever you don't want it to:-)

An established sourdough culture that's always treated well can be stable for many tens of years without invasion. On the other hand any mistreatment (sometimes nothing more than an ill-considered abrupt change in feeding) will allow the culture to be invaded if the invaders are stronger. Commercial yeast is pretty strong and isn't easily displaced by invaders though.

MangoChutney's picture
MangoChutney

 A sourdough starter needs only flour and water, right?
We use juice in the first 3 days to provide acidity that prevents bad bacteria from invading the starter, allowing natural yeast to develop and take over from there, correct?
 
If so, why not use commercial yeast instead of fruit juice? We will hit the same goal.

This is similar to asking why, if we can accelerate the growth of a natural community of wildlife on 50 acres of abandoned pasture by seeding it with a variety of hardy wild plants, we don't instead start by adding a herd of beef cattle.

Commercial yeast, like a herd of beef cattle, is a heavy feeder which grows fast, and this leaves little room for anything else to live on the existing food. The acidity that comes from leaving commercial yeast fermenting for days on end is more likely to be from acetic acid than from lactic acid. The flavor won't be the same as that from sourdough, although it can be tasty.

The beef cattle on the 50 acres of abandoned pasture might reproduce until they over-graze, leaving only shrubs and weeds that cannot support them.  At that point, the cattle might die off.  This would leave room for natural wildlife, who can live on wild plants, to move in.  Similarly, the acetic acid produced in the commercial yeast starter might eventually lower the pH to the place where the commercial yeast will die out and wild yeasts and bacteria can now colonize the starter. At this point we are back to a point akin to having acidified the flour and water with fruit juice, so why not start there?  *smile*

sallam's picture
sallam

You have a good point there. Anyhow, its just an experiment. I'm growing 2 starters, side by side, one with orange juice, and this one with commercial yeast. Time will tell which one will hit the goal of a mature starter first. Besides, I'm not after strong sour taste. I prefer mild sour but stronger yeast power.

MangoChutney's picture
MangoChutney

There is nothing wrong with experimenting.  *smile*

The issues of the strength of the sour taste in sourdough bread and acetic vs lactic acids are entirely different discussions.  There are many ways to make bread, and something is bound to suit your taste.  You might even find that you prefer a totally commercial yeast approach with yogurt or buttermilk added to the dough for a slightly exotic taste.  It won't be sourdough but there is nothing wrong with liking buttermilk bread better than sourdough bread.  In that case, it's best both to make what you like and to call it what it is.

 

Aussie Pete's picture
Aussie Pete

Hi There from Australia,

I have never had success with flour and water to start a colony of S/Dough starter till I read about the pineapple juice starter method and have never looked back. It is started and retained at 100% hydration.

After five days you revert back to using water instead of the juice when feeding it...........has always worked for me.

Pete

sallam's picture
sallam

Thanks Pete for your suggestion. I'm doing a starter using juice, alongside this one. Wish me luck :)

Doc.Dough's picture
Doc.Dough

http://www.thefreshloaf.com/node/10856/

 

Orange juice and pineapple juice are not equivalent when attempting to grow a starter.

Yeast are not acid sensitive over the range of pH 3 to 7.

LAB produce both lactic and acetic acid under different conditions. You smell the acetic acid, you taste the lactic acid.

pH and acidity are not the same; it is quite common to have a low pH and still have only a mild sourdough flavor (ask the folks who are still trying to figure out how to make a more sour loaf).

Be sure to read both Pineapple Juice Solutions Part1 and Part 2.

[edited to correct the pH range over which yeast growth rate is insensitive]

Mini Oven's picture
Mini Oven

so please tell me how pH and acidity are not the same.  Both lactic acid and acetic acid as the name implies, acids.  I learned that anything below 7 (neutral) on the pH scale was an acid and the acid gets stronger as it gets lower and anything above 7 is more alkaline or basic.   

If someone tells me their bread isn't sour, so be it.  I might think differently if I take a bite.   

Chuck's picture
Chuck

My guess is the rather precise meaning of the word 'acidity' we got from chem class just plain isn't the same word as in that post (although it's spelled the same:-). My guess is what Doc.Dough means by 'acidity' is what we'd call 'sourness'. (At least that's how I understand his words "common to have a low pH and still have only a mild sourdough flavor", which suggests that he's using the word 'acidity' to mean something related to  'flavor'.), 

mwilson's picture
mwilson

pH is a good indication of strong acids, lactic, acetic etc. But pH and acidity are not synonymous however. I read an article on pre-ferments recently that says... "

Strong acids dissociate completely into
hydrogen ions and anions, but weak acids
dissociate only partially, and not all of the
acid molecules generate hydrogen ions. pH
measures hydrogen ion concentration and
so gives a good indication of strong acid
concentration but a poor indication of
weak acid concentration"

As for sourness my current understanding is that acetic acid smells sour and lactic tastes sour. I previously thought the opposite but I'm very sure from experience that lactic tastes sour! It's certainly possible to make sourdough bread not taste sour! I'm always doing this, making sweet breads.

But i'm wondering perhaps acetic has less of a taste because it always exists in smaller concentations over lactic.

MangoChutney's picture
MangoChutney

It makes as little sense to argue over whether pH and acidity are synonymous as to argue over whether meters and distance are synonymous.  One is a property, and the other is a unit of measure.

Strong acids are the mineral acids, such as hydrochloric, nitric, phosphoric, and sulfuric acids.  Acetic, lactic, and other carboxylic acids are the ones that are called weak acids.  It is true that weak acids do not dissociate completely.  The undissociated form is in equilibrium with hydrogen ions and the relevant anion.  This does not mean that the pH of the solution has no meaning.  Knowing the pH of a solution of one pure carboxylic acid in water enables one to calculate the concentration of that acid, using the dissociation constant.  In a mixture this cannot be done without further analysis, to determine how much of each type acid is present.  I might point out, however, that the same thing is true in a mixture of strong acids.  Without further data on the mixture, it is impossible to say which strong acids are present in what quantities, just from the pH of the solution.

Acetic acid tastes sour.  Hold your nose and taste some vinegar, or give some to a person with a bad cold, and they will tell you so.  The difference between acetic and lactic acid is that acetic acid is a volatile liquid while lactic acid is a solid.  After baking, all of the acetic acid may have been baked out of the bread, thus giving rise to the myth that acetic acid does not taste sour.  You won't smell the lactic acid in the dough, but it will be there to taste after the bread has baked.

mwilson's picture
mwilson

Glad we have someone like you to give us the sciencey bit!

Just to clarify I certainly wasn't implying that pH of dough had no meaning. If acetic and lactic acids are the weak ones which don't influence pH what acid(s) in soudough cause low pH? 

Interesting point about acetic acid being baked off - I had considered this! Thanks for clearing things up!

EDIT: Also the point about pH / acidity terminology is that pH isn't a whole picture there is TTA too. see this article:

http://www.lallemand.com/BakerYeastNA/eng/PDFs/LBU%20PDF%20FILES/1_11PREF.PDF

MangoChutney's picture
MangoChutney

Weak acids do influence the pH, to the extent that they dissociate into hydrogen ions and anions.  From your own linked reference comes this statement: "not all of the acid molecules generate hydrogen ions".  That means that some do generate hydrogen ions.  The pH of vinegar is 2.2, according to a rather old freshman chemistry textbook in my library.  Vinegar is very dilute acetic acid in water, so acetic acid alone does affect the pH rather strongly in terms of biological organisms.

I am not sure what you mean by "pH isn't a whole picture".  TTA appears to be a measure of the total amount of organic acids in the dough, as opposed to just that part which has dissociated.  One would expect that number to rise throughout the course of the fermentation, and the graph shows this.  pH falls slowly, but realize that pH is a logarithmic function.  For every unit of falling pH, the concentration of hydrogen ions has increased by a factor of 10.  In that graph, TTA has roughly doubled at the end of 3 hours.  It's been too many years for me to shoot logarithms from the hip, and I am too lazy to pull down my CRC handbook, but I would not be surprised to find out that the pH drop shown in that graph represents a doubling of the hydrogen ion concentration over the same 3 hours.  pH is not a sensitive enough scale of measurement for the purposes of the author of that article, and that is fine.  It still remains true that the pH has meaning.

I also note that the article states: "The optimum is 4.2 for gluten swelling and between 4 and 6 for yeast."  It would seem that "yeast" are not insensitive to pH in the range of 3 - 7, whatever species is represented by the word "yeast" is Doc.Dough's post.  The writers of the PDF you have linked to appear to be studying commercial yeast.  It is my belief that wild yeast(s) that grow in sourdough starters are more tolerant to lower pHs than is commercial yeast, but I do not have an actual scientific reference at hand.  However, Debra Wink appears to believe the same thing.

 

Doc.Dough's picture
Doc.Dough

 

The original data to support the pH insensitivity of yeast over the range of 3-7 is in the paper at the link below.  See Figure 2.  This is an important figure in an important paper and if you read it carefully you will see that below pH 4.3, the growth rate of the common LAB in sourdough is less than that of the yeast.  Thus one should be aware of the post-refreshment pH so as to assure that it is well above this point of equal growth rates.  The implication being that a refrigerated starter will produce a lot of residual acid which is not totally neutralized if you use a 1:1:1 refresh. And if this process is repeated enough times, the LAB population will decline (over time) to a point where the population ratio of LAB:yeast is significantly different from a "normal" 100:1. Thus my guidance to use a 1:5:5 or a 1:10:10 refresh of a long refrigerated starter.  This effect is exacerbated by refrigerator temperatures that are not cold enough to shut down the LAB but cold enough to substantially stop propagation of the yeast.

 

http://www.google.com/url?sa=t&rct=j&q=modeling%20of%20growth%20of%20lactobacillus%20sanfranciscensis%20and%20candida%20milleri%20in%20response%20to%20process%20parameters%20of%20sourdough%20fermentation&source=web&cd=4&ved=0CDMQFjAD&url=http%3A%2F%2Faem.asm.org%2Fcgi%2Freprint%2F64%2F7%2F2616.pdf&ei=ni3xToSGBYeuiAL7362yDg&usg=AFQjCNGZ03onGq0dhIbFJJZeuLAIGoW3Rw&cad=rja

 

And to clarify my comment about pH and acidity, I intended that "acidity" refer to TTA (and thus to "sourness").  There is more on this topic in the referenced paper - and a significant parameter which reduces yeast growth rate is not acidity per se, but acetate concentration, with yeast being more sensitive than the LAB (see Figure 3).  So the buffering effects of high ash flours tend to hold up the pH and allow LAB to grow while the acetate suppresses the yeast.  Of the three variables Ganzle examined, acetate is the most significant (as demonstrated by the fact that the relative growth rates of LAB and yeast cross over in the middle of the normal zone) while lactate tends to slow both LAB and yeast by similar amounts and ethanol while it has an effect on both is not seen in most sourdoughs at significant concentrations.

MangoChutney's picture
MangoChutney

I might point out that the yeast under study in your reference above is Candida milleri, which according to the paper is one of the two yeasts predominately found in sourdough cultures, the other being Saccharomyces exiguus.  Commercial yeast is Saccharomyces cerevisiae, which is not synonymous with the two above yeasts and may or may not perform in the same fashion.  Since the original question posted was in reference to promoting the growth of sourdough organisms by seeding the flour and water with commercial yeast rather than lowering the pH to preferentially encourage their growth relative to whatever else may grow at higher pH levels, data on the behavior of Saccharomyces cerevisiae at different pH values would be useful here.

 

Doc.Dough's picture
Doc.Dough

According to the Handbook of Dough Fermentation (Karel Kulp, Klaus Lorenz), p69, Saccharomyces cerevisiae, when added to a sourdough starter culture at densities approximating the resident sourdough yeasts, will die off in two refresh cycles.  This is attributed to the high sensitivity of S.cerevisiae to acetate and thus the incompatibility of S.cereveseae with L.sanfranciscensis in any starter.  Thus the claim that infection of a commercial yeast culture with a cross transfer from a sourdough culture cannot happen seems to be incorrect.  In fact, this would suggest that even feeding a culture based on IDY at short intervals would not preserve the S.cerevisiae for more than a few cycles after the introduction of a viable LAB contaminant.  The question then becomes what yeast survives? And it should give comfort to those who are worried about contaminating their sourdough starter with bakers yeast by using both in the same kitchen.

MangoChutney's picture
MangoChutney

So the lore that is known to those of us who do not routinely purchase $250 references, that the cause of death for Saccharomyces cerevisiae in sourdough cultures is due to dropping pH, is understandable, if incorrect.  It is the acetate anions that inhibit the S. cerevisiae rather than the hydrogen cations.  However, until such time as the acetate anions build up, which is reflected in the dropping pH, the original innoculation of S. cerevisiae will probably hold its own.  Once the acetic acid level is high enough to inhibit the S. cerevisiae, then the other yeasts will proliferate.  Therefore the point remains, that it is not particularly useful to start a sourdough culture by adding commercial yeast to flour and water.

It also appears true, by experimental determination, that acidifying the culture from the start skips the step involving dirty-sock bacteria which confuses novice sourdough culturers. 

And in the end, someone who really wants the dependability of commercial yeast, combined with the flavor of lactic acid, might as well make commercial yeast bread with buttermilk or yogurt.  It won't be sourdough bread, but there is no real shortcut to replace bread made with long fermentation.

Doc.Dough's picture
Doc.Dough

I think your points are all well taken.  The reference cost me a query which found the Google Books reference - I had seen it before - on the first click - so no $250 to CRC, but enlightening just the same in that I uncovered (probably rediscovered) some facts that I had not remembered and thus are new (again). The paper above contains the acetate and pH sensitivity data (also data for temperature and lactate) for the yeast and LAB in conventional sourdough cultures, but does not go so far as to examine the extinction of competing species.

Debra Wink's pineapple juice process seems to be the best alternative to getting a culture from a friend. I don't know why someone would try to start with IDY execept out of ignorance or curiosity. But now, having done it out of curiosity, and being surprised by the result, uncovered my ignorance, which led to a better understanding of the phenomenology.

 

(edited to repair grammar)

suave's picture
suave

It's all fascinating, of course, but in real life I often use a traditional rye bread recipe that starts with old dough (wheat) which is converted to stable rye culture in two 24 hour refreshments.  Also, if you have a copy of "Baking with Julia" you can check it for Steve Sullivan's note on just how quickly and easily yeast preferments will sour.

Crider's picture
Crider

Once the acetic acid level is high enough to inhibit the S. cerevisiae, then the other yeasts will proliferate.  Therefore the point remains, that it is not particularly useful to start a sourdough culture by adding commercial yeast to flour and water.

It is useful to start a sourdough culture with commercial yeast for the very reason that it serves as a perfect gestation environment for the lactobacteria. Rather than wait for the wild yeast to spring up in a straight flour and water medium, the yeast is already there. It blocks the formation of molds and also keeps the dirty-sock bacteria from thriving.

It is sure-fire for those who haven't had success with the usual methods. It approaches the creation of sourdough culture in reverse order: Grow the lactobacteria first, and then the desired wild yeasts will take over. It can also be used right away to produce (non-sour) bread, if that's desired

Aussie Pete's picture
Aussie Pete

Hi Doc,

Never tried or heard of orange juice being used. Only grape and pineapple juices.........should prove interesting.

...Have read the pineapple solution 1 & 2 on this site. Once I read and gave it a go I never looked back......Pete.

Mini Oven's picture
Mini Oven

I was in China with no pineapple juice and bleached flour.  Orange juice was the only unsweetened lower pH liquid I had and I made a starter with rolled oats.   Miracles can happen.  

MangoChutney's picture
MangoChutney

According to Debra Wink, orange juice worked.  It just required additions over two to three days, rather than only on the first day as was possible with pineapple juice.

pH is a precise measure of acidity.  It is the negative logarithm of the hydrogen ion concentration, which is in turn is the definition of acidity in aqueous media.  Sourness, on the other hand, is a perception caused by activation of receptors on the tongue.  It is accurate to say that neither pH nor acidity is the same as sourness.  Because it is a function of an individual's anatomy and sensory perceptions, sourness will also vary from person to person.

Doc.Dough's picture
Doc.Dough

So, having read all of your inputs, but having not done this before, I did as sallam did and built a starter from commercial dry yeast.  I measured the pH after 24 hrs to be 5.10 and started a schedule of feeding every 48 hrs (or so).  This has now been going on since 20 Dec.  It continued to smell like commercial yeast so I had presumed that it had not become acidified by the growth of LAB (and it didn't mold or seem to become infected with leuconostoc or one of the other opportunistic but less acid tolerant LAB).  An hour ago I sniffed it since it was time to feed it again, and it had a characteristic acidic smell.  I checked the pH and it is 3.56 or about where it should be if it is supporting a population of our favorite LAB (or probably any one of the 20 or so that are known to occur in sourdough starters).  I fed it again (4:13:13) and checked to see how much the dilution/neutralization was affecting the pH and post refresh it is at pH 4.97 (close to the 5.10 of the first measurement but depressed by the acidity of the prior batch).  I will continue to observe it (to see when it peaks), smell it, and monitor the pH drop over time to see if the trajectory matches that of my "real sourdough starter", and at some point I will probably bake with it just because I am curious to see what it tastes like. If the time to peak volume is close to that of my other starter, I will feed them both on the same schedule (~12 hr intervals) to have a more synchronized set of measurements.

Mini Oven's picture
Mini Oven

I think once the commercial yeast starter has taken on "wild yeast" characteristics, it is important to raise the feed ratios (as doc has done to about 1:3:3  --  S:W:F or  starter:water:flour)  depending on your temperatures.  

Doc.Dough's picture
Doc.Dough

Mini,

My rationale for setting the minimum refresh ratio is to get the post-refresh pH above ~4.5 so that the LAB population is not decreasing relative to the yeast on a per-feeding basis.

When I got up this morning the pH was down to 3.58 (i.e., the LAB was no longer replicating) but the yeast was still active, so perhaps I have selected a slow yeast with the 48 hr feeding cycle that I adopted somewhat arbitrarily. It smells good but does not (perhaps yet) have the complexity that my regular starter exhibits.

Doc

(edited to clarify "minimum refresh ratio")

sallam's picture
sallam

Many thanks for all your efforts to help me through this, but my starter, like all my previous tries, failed miserably. They never reach double in size.

I've discarded it, along with my other juice starter. I'll remember never to try making my own starter again. Had enough disappointments already. Besides, your great discussions here led me to believe that it takes a patient scientist to make a starter.

I've sent for a dry sample of the 1847 Oregon trail sourdough starter. In the mean time, I'm  currently happy with the slow cold feremtation method that I'm using.

Mini Oven's picture
Mini Oven

maybe it's time to investigate what "failure" entails.  "They never reached double in size," still sounds like a chance to me.  Activity but something missing, something overlooked.  Maybe time to rethink your approach or if the "failures" are truly failures.   What tells you they have failed other than not doubling?  One thing I know, a starter does not have to reach "double" in size to be usable.  "Double" can only be reached when gluten is involved and it has not deteriorated or has not been thinned too much with liquids.  Non-gluten flours or coarse flour will not double but will produce gas as long as the yeast are producing it.   It depends on the situation.  A photo would also be valuable and so would the nit picky details about the starter and it's schedule, feeding, temp, land, etc.  

As you can tell, I don't give up too easy on a starter, the little beasties always seem to let themselves be known.  I remember one very concentrated one that hung under the pH banner just barely puffing along (something like what doc is talking about with low LAB and high yeast.)  "Just about dead" said the owner... until someone suggested a feed ratio of 1:5:5 and POW!  It took off much to everyone's surprise.  Another was perfectly fine, and the maker continually threw out the starter when they thought it smelled bad.  What wasn't known is that the starters were just fine, the maker just didn't know what a sourdough culture should smell like.  When the starter needed feeding, it got thrown away instead.  So...  maybe something simple is being overlooked or assumed.  Go back and question every conclusion that turned into "fail" and ask questions.  Don't ditch a starter too early.  When every effort is not working, then I begin to suspect major problems not involved with flour.  Location, strong sunlight or UV light, cleaners or sprays, alkaline water, salty water, chlorine, utensils, cold, heat, drafts, dioxins, equipment, sabotage...