The Fresh Loaf

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How different is one starter from another?

bwraith's picture
bwraith

How different is one starter from another?

I've read a couple of recent comments by Mac, and sphealey, and others about the origin and character of sourdough starters. I'm still wondering what's the real scoop. I've read from highly authoritative, credible sources several different versions of various arguments about sourdough culture organisms and their origin and survivability in a culture.

I'll try to summarize the gist of them briefly:

1) There are only a handful of organisms in the world that will live in any sourdough starter. Therefore, there is not that much variation from culture to culture once they stabilize.

1a) It's more how you maintain the starter that determines which organisms are favored and active, and therefore what the flavor will be.

2) A geographic region's environment results in only certain characteristic organisms living in the sourdough starters in that region, so the flavor varies by region. You really can't maintain the character of a starter originated from a different region because it will inevitably be taken over by the organisms of that particular region.

3) You can maintain a sourdough starter's initial organisms if you are careful not to contaminate the starter. The character of the starter will continue indefinitely if you do that.

4) The yeast and lactobacillus bacteria come from the air into your culture.

5) The yeast and lactobacillus bacteria come from the skin and microenvironment of the kitchen into your culture.

6) Yeast and lactobacillus bacteria only come from the flours that go into the culture.

7) Yeast and lactobacillus bacteria can be contributed from raisins, grapes, yogurt, and other additives to a culture.

8) No, the organisms on grapes, raisins, yogurt aren't really the right ones and would do nothing or perhaps even contaminate and delay the development of a healthy culture.

9) Other? I've probably left some key argument out of the list above.

I'm wondering if any members of this site can put a finer point on this. Which of the many sources which make widely differing and often contradictory arguments should be considered most credible and why? What about personal experience or experiments you've done? Do you have any real examples where two cultures supposedly of different origin are maintained in the exact same way and yet taste very different? I'm looking for credible scientific evidence or definitive experiments people have done themselves and can attest to, if possible.

Bill

TRK's picture
TRK

I am not sure why this discussion has to happen off the board, so somebody PM me if this is a sore topic, but it has been something I wonder about off and on as well.  I tend to subscribe to 2, 4, 5, and 6 on the list above.  I think that the yeast and bacteria come primarily from the grain, but also probably from the air and from us.  I think that once they are established, they will probably change their character if you move to another geographical area, though my starter, begun in Oregon, has pretty similar properties here in CA.  If you used perfect sterile technique (i.e., autoclaving your container, using an airlock, sterilizing everything before it touched the starter) I am sure that you could keep a starter pure when you move it to another environment, but that seems like an excessive amount of work for a relatively minor change in your bread, IMO.  I tend to agree with authors who suggest that the best yeast for growing in cereal are those naturally found on cereal grains, rather than on grapes, or milk, or whatever else people add, but I doubt they do much damage. 

 

For excellent sourdough microbiology information, I recommend The Bread Builders by Alan Scott and David Wing.  The appendix, in particular, goes into a lot of detail, though not so much about sources and species composition, which seems to be what you are interested in with this question.  

 

I guess that is kind of short of scientific evidence, but those are my opinions based on pretty extensive reading, and the microbiology I learned in graduate school.  I'd love to hear other people's thoughts.

 

Tim 

bwraith's picture
bwraith

Tim,

As far as I know, this is not a sore topic, nor are we trying to move off list. The reason for the email exchange was more that I was hoping to get Mac to email me a starter recipe he says he likes.

Meanwhile, I just recently got "The Bread Builders", but I have yet to pay any attention to the appendix, so thanks for pointing me in that direction.

I'm also not trying to discourage all but strict "scientific evidence" in this discussion. However, I was hoping that there might be some participants here with strong backgrounds in biology and/or who have read the technical literature more extensively who might be able to clear up some of the contradictions, explain their origin, and point to which of these various proposals in the initial post are most likely to be true.

Also anyone with who may have done some experimenting on their own that clearly points toward one or the other proposal being true is interesting.

It's just that in the reading I've done, especially when you browse around on the internet, you just discover an amazing variety of statements, and it's almost impossible to assemble it into a decent picture of what's really true.

Bill

gumby's picture
gumby

Hi Bill,

That's an interesting subject that you brought up. And one that I was curious enough to do research on before.

I'd like to share with you what I've learned. 

Options 6 and 7 are the correct ones. 

The surface of grains, vegetables and fruits are covered by lectins. Lectins are a natural part of the surface of the plant. Humans have lectins as well.

Lectins are proteins that bind carbohydrates to them.

Lectins on plant surfaces will bind specific beneficial bacteria and yeast to them. Scientists believe that they do this in order to prevent bad bacteria and yeast from attaching to the plant, and destroying it.

There are a large variety of different bacteria and yeast that can bind to wheat, rye, grapes, etc. And they are not always the same microbes between plant type. Or even within specific grains, such as wheat.

However, for our purposes as bakers, it is enough to know that the types of bacteria and yeast on the grain surfaces are the same ones that cause the sourdough to ferment. This is why it is far easier to make a culture from whole grain flour than from white flour.

If the lectins bound bad types of bacteria/yeast/mold, such as E. Coli or aspergillus flavus the sourdough would smell very foul, and be highly toxic. 

It is most likely a protective measure that the grains coat themselves with the beneficial microbes. 

That is why you should pick out any moldy grains, since they are contaminated with the wrong types of microbes.

****

Flavors from various sources

You can use a wide variety of grains, vegetables or fruits to generate different types of microbial cultures. Rye is well known to bind many different types of microbes beneficial to bread making. 

Fruits are often also used, since they are well known to have yeasts attached to the skin. That was discovered a long time ago, since in order to make wine/alcohol, all you need to do is take fruits, crush them to extract the juice, and at the same time, the microbes from the peel are also mixed into the juice. And then fermentation takes place within a couple of days. Which shows the presence of large amounts of yeast on the fruit surface. 

I've made cultures from a few sources. One that developed quickly and was almost explosive in power was a mixture of brown rice and a black indian bean called Urad dal. This mixture is used to make a fermented dish in south India. Again the microbes come from the skin surface.

Bean skins also contain a large quantity of beneficial microbes.  If you have ever soaked dried beans in water for a few days, you will have seen that the water starts bubbling and foaming after about 1.5 to 2 days. Due to microbial action. 

So many things can be used to generate a strong ferment. And the neat thing is that the microbes will vary incredibly depending on the source. As a result they will have different rising speeds, as well as tastes.

****

Different tastes

Why do yeasts and bacteria develop different tastes in dough?

Dough is composed of different types of complex carbohydrates. As well as proteins, and other components. 

Basically, different types of yeast and bacteria have stronger or weaker abilities to break down vegetable matter. For example, some can break down cellulose or hemicellulose, some can't.

Each bacteria or yeast has their own ability to break down different grain components. Once they've done this, they ferment it for food, which produces gas and alcohol in the case of yeast, and acid and other byproducts in the case of bacteria. 

There are parts of the wheat that aren't broken down, which is why the dough still remains basically the same consistency and doesn't completely liquify. Only a certain % is fermentable. 

But amongst microbes, there are different abilities in fermenting, what types and how much. Also the byproducts of fermentation can be quite different. This causes differences in taste. 

**** 

Culture Stability 

If the same culture ingredients are used until fermentation is under full power. For example brown rice/black beans are only used until the fermentation is full.

And only at that point the wheat is added. Then the culture can remain stable fairly easily. The reason is that there are many many times more microbes in the culture than there are on the surface of grains. I am not a microbiologist, but I would guess millions of times more by the time the culture is in full force. 

So although new microbes are being introduced to the culture, there number is proportionately insiginificant, and the culture would quickly eat up the available fermentable components of the dough. And not allow the new species to develop. 

I've seen research from italy where microbiologists examined the species in various cultures and was impressed by the huge variety in species.

Scientists speculate that the microbes that form the culture live in a symbiotic relationship that keeps other foreign microbes from developing substantially.

It is hard to see in bread, but with fermenting milk, the differences between microbial cultures is much more obvious. We all know about yogurt, but there are other types of ferments, such as kefir, piima, fil Mjolk that all have unique properties. Not only taste, but texture, ropyness.

Some cultures, like kefir are a mix of bacteria and yeast. And even when raw milk is introduced to the culture. (Which contains large amounts of beneficial bacteria). The kefir culture still maintains it's physical properties and taste. 

If the kefic culture were being contaminated and changed be the introduced bacteria from the raw milk, it would change in both flavor and physcial qualities.  

This shows that the Kefir has the ability to maintain its original bacterial/yeast symbiosis.

This agrees with research done on cultures, such as the San Fransisco. Which consistently shows that the culture remains the same over the years, and effectively resists contamination from bacteria and yeast introduced from flour. 

Hope that helps.  

Gumby 

 

 

 

 

bwraith's picture
bwraith

Tim,

I think I pretty much intuitively believe the same 2,4,5,6 above. However, I changed 1 to have a 1a, because I think Mac said this, and I have a strong feeling he's right, that 1a is true. I think (1) itself is very interesting. Mac had at one point said there are only a few organisms, but how few, and can you get different compositions based on the initial inoculation that then remain stable and change the nature of the culture.

I do think it makes sense that if you are constantly introducing flour and water and not using perfect sterile technique that eventually you probably would introduce some new organisms into the culture, which would change whatever you started with. However, I've read some things from SI literature that seem to contradict that. How careful do you need to be to avoid contamination, and is it possible that initial organisms have any capacity to reject organisms that are well adapted to a starter environment?

Bill

TRK's picture
TRK

Bill,

My first instinct is to be somewhat skeptical of SI literature (I am assuming you mean Soudough International) both because they have an obvious commercial interest in being able to keep a strain pure (after all, why buy multiple strains, when they are all going to end up the same as what you could capture yourself eventually), and because they seem to be one of very few voices making that claim.  I have hardly done an exhaustive study, but I have done a lot of reading on the subject, and most other sources seem to be saying some variation on the idea that your starter eventually reaches an equilibrium with the local fauna.  I have done some lab microbiology, and knowing how difficult it is to keep out contaminants when using sterile technique, I just have a hard time with some of those claims.  Unless you assume your flour and water are sterile (or irradiate and boil before you use), even perfect technique won't keep a pure culture.  I suppose the argument could be made that a stable culture will out-compete introduced organisms, which is a possibility, but I would need some serious evidence before I would believe it.

The idea I would be willing to accept, however, is that an existing starter might contain organisms that would not be found in your environment, which could persist in a mixed  culture with other organisms even after new ones were introduced.  So a starter that began with one purchased from SI that came to equilibrium with my local fauna might still contain organisms that it would not have had otherwise, because they were allowed to establish in the original starter and persist even after "contamination."  

I think that Mac is probably quite right with the idea that the conditions you subject your starter to (type of flour, degree of hydration, temperature, frequency of feeding) can cause differences in flavor and leavening power.  Of all the things we can control, that seems most likely to be able to alter the way it behaves.  I could do an experiment with this.  I already maintain my starter on whole wheat and white flour (captured on rye, fed on white flour, kept at 100% hydration all along), and could add rye, and vary the hydration to see if I get different results.  Unfortunately, I am not sure I have the time to do an experiment like that right now, but I like the idea.  

 

Tim 

mountaindog's picture
mountaindog

Great topic and nice summary of the various theories I've come across as well. I'm also interested to know what others conclude from all of this. The Bread Builders was also a great source of this type of info for me, and some of the same info by the Austrian researchers is posted by Dan Wing on the rec.food.sourdough newsgroup. I tend to ascribe to numbers 1, 1a, 2, 5, 6, and 8, but I also realize there may be some contradiction between 1 and 2, unless it is just the distribution of the limited handful of organisms that account for the regional differences. More info would be welcome...

Mini Oven's picture
Mini Oven

Now that I've got my Austrian SD going, it would be interesting to take it back after 6 months and make two identical loaves and see if the SD has changed in flavor.  Two very different environments.   I tend to agree that different environments affect SD developement.  I also think that environments can also change with time and thus change the SD from one particular area.  But I also think the lactobacillus and yeasts are just about everywhere the fermenting ingredients can be found. I think different cultures have their favorites flavors so tend to instinctively choose methods that favor their development through experimentation and observation using different water, weather, ingredients, altitude, and time for such experiments. What works in one part of the country doesn't always work in another.   We also choose as we throw away something that to us smells bad trying "next time" not to repeat it.  Wouldn't our experiments be really fun if we could smell on the internet?  And each other's cinnamon rolls?

bwraith's picture
bwraith

MiniOven,

That's exactly the kind of experiment I'd like to know about. I don't know if you kept a backup of the Austrian SD that would allow you to re-create the original culture, but it would be very interesting to hear the results of comparing the taste and rising properties of two cultures maintained in exactly the same way, one fairly newly generated from the original, and one 6 months old.

As far as being able to taste and smell over the internet, maybe Floyd can develop a drupal plugin for us. In addition to the camera and the tree icon we could have a tongue and a nose in the comment composition window.

Bill

ehanner's picture
ehanner

If it is true that the La Brea Bakery in LA won the San Fran "Great Sourdough Bread Contest" not once but several times, I would say it doesn't matter if they are different cultures.

I think this is one of those situations where we "Measure it with a micrometer, mark it with a grease pencil and whack it off with a chain saw".

I want to understand how to guide the flavor depth using all the tools that La Brea has at it's disposal.

Eric

T4tigger's picture
T4tigger

I have 2 starters that I'm comparing.  Boris is about 6 months old, and was created in my kitchen with rye flour and water.  In all the time I've had him, he has never doubled in less than 8 hours no matter what ingredients, proportions or schedule I used.

Dusty is 2 weeks old, started with the same rye flour and water but incubated for his first 3 days out in my garden in 65 degree temperatures.   He is extremely active, and will double in less than 3 hours on a regular basis.  

To experiment, I have been feeding them both the same thing at the same time in the same proportions and storing them right next to each other to ferment.   Dusty still fills his jar well before Boris seems to wake up.  

The only difference I can think of is that Dusty picked up some bacteria from the yard that Boris didn't find in my kitchen.

Any other ideas to explain the difference?

Colleen 

bwraith's picture
bwraith

Colleen,

I agree that's the kind of interesting real example I've been wondering about. At the moment, I'd be somewhat skeptical that it's just some difference in the early going, although even that is pretty interesting since you used the same ingredients to start it. What would be fascinating to see is if that difference will persist for another couple of months, if you intend to keep them both. I hope you do, because I'd like to know how that turns out.

Bill

zolablue's picture
zolablue

so just give it a try.  The necessary microflora are present in white flour but just not in the same amounts.  So definately it can be done. 

You are much deeper into this than am I.  I just posted the Glezer firm starter recipe with the photos I took showing the expansion of that starter in 8 hours.  It has really been so easy for me using this method and delicious tasting bread. 

I can't begin to understand some of the minute nuances of this and I guess, luckily for me, because I haven't had a problem with the starter I chose to create.  I just gotta bake more bread! :o)

bwraith's picture
bwraith

Zolablue,

I'm still hoping someone can say why, if the organisms are less populous which seems like a compelling argument for whole grains, there are experts who seem to recommend staying with only white flour for the whole process.

I agree that it's nice to be on to the bread making stage. I've been there for a couple of years with just the one culture, other than a KA SF culture I keep around and use occasionally. Everything couldn't be easier at this stage. However, when I got started, it was torture, more like what L_M is experiencing, as an example. I'm virtually certain it's nothing about my procedures. I've been extremely careful in every way I can think of. However, it's amazingly repeatable for me - stinky in first 24 hours followed by very dead culture for a long time. This seems to be the case with different KA flours I've tried, too.

It's frustrating because you hear in posts from some experts who obviously don't have the problem a kind of dismissal: "It's easy, 5 days, nothing to it, can't fail...", like I'm just not doing it right and must have something wrong with my process. However, it just doesn't seem to work that way here in my kitchen, and I've seen lots of posters who I believe probably also were extremely careful and have described similar problems.

Although I have a very stable working culture, hanging out w/L_M and talking about this stuff with you and others here has me all fired up to go back and try starting some starters again. This time, I'm more knowledgable than when I first did it, so I think it'll be much more interesting, and there's always the chance I'll finally discover the key things that will make my process work right in my kitchen with more reliability.

As I said the big key I found two years ago was acidifying the first day mix. It made a huge difference.

Bill

JMonkey's picture
JMonkey

Just about any flour will work. MiniOven made one with oats, if I remember correctly. A very popular sourdough page for beginners uses white flour. Personally, I've had the easiest time starting with whole rye, but I think they'll all probably work eventually. These sourdough critters are everywhere, it seems.

zolablue's picture
zolablue

I found my firm starter reacted exactly as Glezer predicted and on time.  Even the short time it was to smell not so pleasant was only a day or two and then it became extremely delicious smelling. 

The only thing I experienced after that was my starter took a lot longer to get its strength to be able to take down the ingredient amounts called for, I think, for a couple reasons.  One, it was a young starter, obviously, and it was extremely frigid - I mean, crazy cold outside and our kitchen temps were generally around 68 to 69 degrees.  A firm starter does better in warmer temps so that difference was obvious once it started to warm up here. 

Having said that, I still have not taken it down to its final refreshment of using the 10 grams starter.  I'm still using 15 grams and it is quadrupling easily within the 8 hour time frame and raising bread so I'm happy with that.   

ehanner's picture
ehanner

We could purchase a 5 pound bag of rye or whatever flour and divide it into say 5 ziplocks and mail them to 5 members who have an interest. Everyone should use the same process and acidifier. Make notes and take photos and let's see if there is a local impact. A pound should be plenty to get past the critical stage. Actually the last time I did this a single serving can of pineapple juice was plenty for three days, that could be included in the starter kit.

Anyone interested in trying this? I would be happy to put the packages together and mail them.

Eric

bwraith's picture
bwraith

Eric,

I'd like to try a test. If it helps simplify things, I'd be willing to foot the bill for some number of kits.

Bill

ehanner's picture
ehanner

I sounds like there some people who have trouble getting the same results as others. All things being equal, except the environment (local, kitchen, heating system, water to name a few) the results should be similar. The group can determine routine feeding schedules and such things like temp. I wouldn't thing it would be a good idea to sterilize the juice or anything else. Sooo, anyone else interested in participating? If so state your ideas about how we should proceed.

 

Eric

Mini Oven's picture
Mini Oven

Sounds like a fun experiment.  I love to be part of it but fear custom regulations might not allow it.  

I am really enjoying my Austrian sourdough.  All other SDs I've come up with over the years, just can't compare.  The egg size ball that I got from the baker (I think it had already been diluted when I got some) was normal dough consistency and I added some flour, pinched and dried it into flakes.  When I arrived here in China.  I had no oven but I scrounged around and came up with one and took half of my flakes (yes, Bill, I'm cautious) and put them into some water, later that day, added a tablespoon of flour and let it rest.  It was very cold in the Apartment, 13°c and so I moved it on top of the VCR for a day.  Nothing.   No smell, no sour and hardly a bubble.  

The next day, I was keeping my mixture loose to give all those good little beasties lots of space to do their thing, I gave them another tablespoon of AP chinese white flour and another spoon of bottled water... and then I added a scant teaspoon of grapefruit juice. (yea, I know, just when you thought oj and pineapple were the one and only lovers of the "beasties") sorry, but that seemed to do the trick and they took off.  Bubbles and sour, then more flour to thicken things up and let em feast on that for a day or two.  They soon were back in the kitchen and I checked on them now and again.  I could now build them up and I liked the idea (thank you Fresh Loaf) of keeping them thick with flour.  They seemed to make everything more liquidy on their own.  As I have low gluten flour, I didn't rate them on how high they rose, if they got bubbles and smelled sour, then they're doin' it.  Since it was cool, they took their time also. 


By the time their weight reached one fifth of my loaf weight, I saved one tablespoon of the sourdough paste for later, and threw the rest into my dough.  Meanwhile the heater was fixed and the apartment temp rose to 20°c.  From start of dough to finished loaf was 24 hours.  It didn't start really rising until the following day I parked the bowl over a pot of cooling boiled water, plate and towel between (didn't want to cook my beasties, just warm 'em up) They doubled and then I floured and folded.  That was one gooey mess!  Gave up trying to fold and changed to kneading another 5 min adding lots of flour.  Then I shapped it and threw it into my casserole, put the lid on and back to the warm spot. 6 hours later it came out of the oven. 40 minutes at 225°c.  Had a crispy cracked top crust and sour smell.  No misteaking the smell.  After that loaf I was baking pizza bread to be made into pizzas later, and the difference was obvious!  But would the sourdough taste sour?  The next day, I cut some for breakfast, just plain, and simply bit into it.  Wow....

If I didn't know it was made from only white flour, I would swear it was anything but white, very nutty, with hints of rye.  I didn't add any spices.  I wanted to taste just the sourdough.  Also good with cream cheese.  And sour.  My "not so thrilled about sourdough" husband loved it and kept asking for more.  It really is incredible.So when I compare my starters, the others fall far behind.  I will go re-start my oat SD flakes just to make a comparison.

ehanner's picture
ehanner

What a great story mini-oven. I admire your ingenuity in a difficult situation. You must be somewhat of an oddity making wheat breads. There isn't much of that in China or the local diet. May I ask how or where you got the starter?

Eric

Mini Oven's picture
Mini Oven

I got a sample from my favorite Huber Baker in Leonding, Austria. They have always had fantastic bread. I travel back and forth. Right now, I'm north of Nanjing, China.  
It is kind of fun looking for flour.  Got me started on trying all kinds of grains I never had tasted.  I identified many with this link
http://www.purcellmountainfarms.com/index.htm

I have now soaked my SD flakes made June 21 2006 as mentioned in my blog.  I see by my notes there is a bumpy road ahead if I can activate them.  I'm keeping them on the opposite side of the kitchen and added just a wee bit of orange juice.  My Austrian SD is behaving like a good starter and doubling size within 4 hours.  It's very consistant  and will feed it again tonight to bake tomorrow.   
We've been hit with a heat wave.  Temp daily rise to 26°c and windy.  I've had a head cold for 3 days, and don't really feel like baking but I've run out of bread.  Think I'll cook up 100g of Barley berries to throw into dough and mix early to bake in the evening.  Probably better to mix dough tonight and chill it but there's no room in the fridge.    :) Mini Oven

Mini Oven's picture
Mini Oven

Who an I trying to kid?  I put my Austrian SD into the fridge and have to laugh at myself.  Barley berries?  I ment Buckwheat but I don't even have any.  Prdicting temp of 30°c today and the news reports a case of bird flu in the northen part of the province.  Yikes.  There is always rice...  Good night.... Mini Oven