The Fresh Loaf

News & Information for Amateur Bakers and Artisan Bread Enthusiasts

Two questions about pre-ferment

hansjoakim's picture

Two questions about pre-ferment

Hi all,

I made Hamelman's beer bread the other week, and found it absolutely delicious. Now, his recipe calls for a straight poolish as a pre-ferment. I was wondering if it would be possible (or desirable) to put beer also in the poolish, thus replacing the entire water content of the recipe with beer? Do you think that would improve the taste, or would the pre-ferment end up stale smelling and... not really worth putting into your loaf?

On a related note, a friend of mine asked me about the possibility of starting a "sourdough" starter using a speck of commercial yeast added in the early stages of the development. To me, this sounds like turning a poolish or biga gradually into something of a "sourdough" equivalent... would it work? I guess it should work, right, as long as you add just the tiniest bit of commercial yeast, and ensure that the yeast is fed and happy. As time elapses, it would gradually become a "true" sourdough starter. I'm no expert on the microbiology involved, but it sounded quite plausible to me. What do you think?

Have a nice weekend everyone :)

Mini Oven's picture
Mini Oven

fella, just the kind of fella a starter would need to get started. So start a starter, or get one from a friend. Where are you? I'll send you one, but not with commercial yeast, it would just be a waste of good time and effort. Go for the real thing. It will be "true" from the start.

Have a nice weekend too. :)

Mini O

Edit:  Norway, well that does make things a little trickier.  How about you go buy some sourdough off your local baker.  All you need is a tablespoon or so.  You might have to wait a day so get onto it asap.   

hansjoakim's picture

haha :) well, if you say so...

 regarding the starter: i wasn't planning on making a starter that way, but the question from a friend of mine got me curious if it would work. on the web, you read about lots of botched sourdough starter attempts. i was thinking this could be a slightly more "bulletproof" way of getting one going (although it could be regarded as cheating/doping)...

Mini Oven's picture
Mini Oven

about problems.  People who don't have problems with their starter won't look for solutions or go on about it not working.  I think there are many out there who are not having problems with their starters.   And there are those who just like to experiment and tweak their starter even when they work, always looking for the perfect loaf. 

SO if you want a sure fire way, go get a sample from a good baker and take it home and feed it when it is ripe.  You also have a good supply of whole grains where you are?  Then it should also not be a problem to start one. :)

Mini O 

subfuscpersona's picture

For the price of two stamps, you will get about a tsp of dried sourdough starter from the friends of Carl Griffith. The web page with all the info is

I just used it to make a sourdough starter and it works well.

Tell your friend not to bother with trying to create a starter with commercial yeast. Get the real thing.

Mini Oven's picture
Mini Oven

Really now, Just because commercial yeasts were developed to make baking easier and rising time more reliable, doesn't mean we can't use them. Lets just not call them sourdough.

I can't proove it but I think the commercial yeast will dominate the culture and not allow for any other growths to take place until it has died off. Sure it will give a flavour to bread but it will be is a lopsided development, all yeast and it's by products.   It is a different kind of flavour. It is better to get the lacto beasties going before the wild yeasts and this is what happens when developing a starter from flour and water.

Mini O

hansjoakim's picture

good point, mini o. quite a few of my cooking books call bread made from starters with commercial yeast "sourdough bread". there's an important distinction between bread made from pre-ferment and bread made from a proper sourdough starter.

and it sounds like you've got it right when it comes to the cheating/doping topic. at least it makes good sense to me! thanks for your replies :) 

Mike Avery's picture
Mike Avery

I get lots of emails from people who have trouble starting sourdough starters. Most of them read books, talk to friends or use other web pages. And then I get to help them (which I enjoy doing).


In "Breads from Laurel's Kitchen," Laurel talks about starting a sourdough starter using a speck of bakers yeast because it will "attract" wild yeast. *sigh* The two major things wrong with that suggestion is single celled critters don't have the ability to decide where they are going or to influence where they go. They're not birds looking for a bird feeder! Also, the critters in the culture are pretty much already on the flour. It's a good whole grain book, not so good a sourdough book.


I believe the name "sourdough" comes from the German "Sauerteig." Sauer in German means "acidic" and acidic may be a better description than "sour." Some sourdoughs are sour, some are not. However, all should be acidic. How sour they taste depends on the acids the culture produces which depends on how the starter is handled, what the starter is fed, and the critters in the culture.


The acidity thing is important here. Bakers yeast can not tolerate the acidity in a healthy sourdough culture. Bakers yeast will cause the culture to bubble and rise. And then as the culture's sourdough bacteria become more active, they will kill the bakers yeast.


When the bakers yeast is killed off, the starter will slow down until the wild yeasts that can tolerate the acidity take over. If you read Rita Davenport's disaster of a sourdough book (it might be a good baking book, but it is not a good sourdough book), her answer is to add more bakers yeast. Not a sourdough answer. 


The sourdough answer is to start the starter with whole grain flour and water. And to encourage the growth of the critters you want from the git-go.


Similarly, some people suggest using cabbage leaves, grapes or other odds and ends to start the culture. While both cabbage and grapes have yeast on them, they aren't the right sort. The culture will start up, stop, and then start up again. Some people say the grapes provide food for the yeast. Well, yeah, but it's the wrong food. Flour is the right food.


So, just enjoy the cabbage or grapes - you'll get more out of them than the starter -  and start a starter with flour and water. It'll work faster.


Please note, this isn't to say you can't start a starter with yeast, cabbage leaves, grapes or whatever. Just that those aren't the most effective or efficient ways.




Mini Oven's picture
Mini Oven

And I bet you really wanted to know more about the beer than the yeast.  Well, try it and see.  Beer can be pretty sweet stuff so some kind of compensation must be made.  I might lead to early deterioration of the dough as you suggest, but hey, you only live once.  I suggest using a hard wheat that can handle the abuse. 

Mini O

Bakeract1's picture

If you use all beer, the yeast will have a tough time fermenting. In other words alcohol tends to suffocate the yeast. Using water in the poolish will give the yeast a good strong start.

As far as using commercial yeast for a starter, I think Mini O is right. You shouldn't add yeast to start a sourdough. 

Commercial yeast (S. Cervisae) contains about 5 billion cells per gram. Wild yeast (S. Exiguus ) has about 10,000 per kilo of bread flour. Because sourdough relies highly on the fermentation of bacteria, it can never be the same if you add comercial yeast as if you don't. S. Exiguus has a higher tolerance to the acid produced by the bacteria that gives the distinct flavor.

keesmees's picture

did many experiments on sourdough with a bit of yeast added after a few days for 'pain au levain', but:

it is very difficult to keep your sourdough-culture clean and stable, even when you add only a speckle of yeast in it. it takes some time, but in the end the  yeast always undermines the acid which keeps the sourdough-starter healthy.  

so, I changed tactics and nowadays I use a sourdough starter in the biga/poolish the evening before and add a bit yeast in the final dough next morning.

I like fresh bread at lunchtime, so I steer (stretch) the the final process with a bit lower temperature and a small amount of yeast.

this way even the 50/50 spelt/wheat dinner rolls are airy and have an elastic crumb.

(on the beer I can't help you)

grtz kees