Yeast after poolish questions

[donstavely]

My standard (amateur) dough recipe uses a poolish with the requisite small amount of IDY.  I know some folks rely only on the the yeast grown in the poolish, while others (including Tony G.) add yeast in the final dough.  My understanding is that both techniques are valid -- that the extra yeast is "insurance" in case the poolish is over-fermented and its yeast is no longer active.  First question: Do y'all believe that this explanation is true? 

Per Tony, I use 0.5% along with the poolish.  But, I have noticed that sometimes my dough seems very active right after mixing, starting to rise immediately before going in the fridge, and continues to rise as it cools down.  Other times is requires a hour or more of rest at RT before any signs of life, then rises very little in the fridge.  Which begs the second question: Could the difference be explained by the above implication -- i.e. that in the former case the poolish yeast was abundant and thriving, while in the later case the the poolish yeast was "spent" and it was only the "insurance" yeast that was working, albeit more slowly.  I have not tried to make a science project out of it, so there may very well me other variables at play.  For instance, my RT in winter is about 70F, while now in summer is more like 75F.  What do you guys think?   

Note that I am intentionally not listing my full process and percentages because I am interested in learning general principles, not specific troubleshooting of my dough.

   

[scott r]

Yes, an over fermented polish will not rise the final dough as fast.

[donstavely]

Still wondering if others have had similar experience with wildly variable final dough activity, depending on the maturity of their poolish.  Recipes are very precise about yeast amounts, times, and temperatures.  Yet with as much variability as I see, it seems the operative word is flexibility to deal with a wide range of activity levels.  No?

 Also, wouldn't folks that do sourdough have the same issue -- perhaps even more-so?  I guess I can understand in a commercial environment where the process is perfectly consistent.  But for amateurs, how do you gauge the activity of the starter?   

[TXCraig1]

I think it's a bit different for SD. Nature has designed the flora in a SD culture to propagate. Scientists designed commercial yeast to give big, fast, consistent rise, but it's more of a once and done thing. I don't think there is much propagation going on in a commercial yeast preferment.

[donstavely]

Scientists designed commercial yeast to give big, fast, consistent rise, but it's more of a once and done thing. I don't think there is much propagation going on in a commercial yeast preferment.

Hmm, I am confused, Craig.  I thought that all yeasts grow exponentially, at least until they run out of nutrients, or their environment gets toxic (alcohol, acid, etc.)  This is why even the smallest pinch of yeast in a poolish will eventually grow into a gooey bubbling mass -- as will more yeast in a shorter time.  Isn't this right?

Next questions:  What happens to the yeast when a poolish becomes over-fermented?  Is this the point that the yeast has run out of nutrients?  Is it when it is still growing, but beyond the limit of the gluten to support the expanding CO2?  Does the yeast die, or just become dormant?  Will it revive when added to the final dough without additional yeast? 

It still seems to me that these same questions apply to a sourdough starter as well as a poolish.  Can the starter be considered a poolish that is continually over-fermented, used, "re-animated" with more flour and water, and then over-fermented again to propagate it?

Sorry if these questions are elementary, especially to a sourdough baker.  I would like to try it sometime.  I think I need to need to understand and tame my poolish before I graduate to sourdough!      

[TXCraig1]

Growing is not the same as propagating.

[donstavely]

Growing is not the same as propagating.

Well, that explains everything! 

Would anyone be willing to offer some more verbose answers to my questions in the previous posts?  I am honestly not trying to be obtuse.

[TXCraig1]

Propagating is cell division, when the yeast multiply. It basically doesn't happen with commercial yeast in an anaerobic environment like a poolish or dough. Fermentation simply can't provide enough energy for commercial baker's yeast strains to do it.  It does happen with SD cultures however. My only point is that there are additional complexities introduced with SD.

[donstavely]

Thanks Craig.  That makes sense now. 

In hindsight, I shouldn't have tried to make the analogy between poolish and sourdough.  I clearly should have kept my questions focused on my own OP about poolish.

[RHawthorne]

Not having any details about your recipe, it's impossible to give a lot of meaningful input on exactly what you should or shouldn't do differently. But I would say that if you're going to add more yeast after the poolish, 0.5% sounds like rather a lot to me, no matter what you're doing, unless you're going for a very short fermentation time after incorporating the secondary ingredients. You should have already gotten a good healthy head start with the poolish, and adding that much more yeast should not be necessary. That's more than a lot of people use even without a poolish.

[Yael]

[...] I know some folks rely only on the the yeast grown in the poolish, while others (including Tony G.) add yeast in the final dough.  My understanding is that both techniques are valid -- that the extra yeast is "insurance" in case the poolish is over-fermented and its yeast is no longer active.  First question: Do y'all believe that this explanation is true? 
[...]

Yes, I agree with this explanation. It's all about your constraints and preferences: last time I made some bread using a poolish. I added a little amount of yeast in the poolish, but it wasn't enough and the second day the poolish was ready later than expected (say at the end of the afternoon instead of the morning), however I still needed the bread the evening of that day, and I just had 3H of possible fermentation left. Well I adjusted the amount of yeast needed in the final dough so my bread would rise during these 3H. If I haven't added any yeast in the final dough, maybe it would have taken another 10-15 hours.

[...]Which begs the second question: Could the difference be explained by the above implication -- i.e. that in the former case the poolish yeast was abundant and thriving, while in the later case the the poolish yeast was "spent" and it was only the "insurance" yeast that was working, albeit more slowly. [...]

Differences in temperatures (room temperature, ingredients temperature...) and in yeast quality (even within the same bag) can bring differences from a fermentation to another. If the poolish is overfermented it's possible that a part of the yeast already became inactive/dead. But that's one of the advantages of these pre-ferments, even if it is in bad shape we're only talking about half the dough, and we'll have a brand new half soon that will heal everything 

[donstavely]

But I would say that if you're going to add more yeast after the poolish, 0.5% sounds like rather a lot to me, no matter what you're doing, unless you're going for a very short fermentation time after incorporating the secondary ingredients. You should have already gotten a good healthy head start with the poolish, and adding that much more yeast should not be necessary. That's more than a lot of people use even without a poolish.

I started my "serious pizza journey" with the Tony's master dough recipe in the Pizza Bible, which uses 1% yeast with no starter and 1/2% with starter.  I would agree that this seems too much, given my most recent experience with a super-active dough.  I  know that my poolish looked great - triple volume, jiggly and bubbly and not collapsed. 

On the other hand, it sure didn't seem like too much added yeast in my last batch, which seem very sluggish after mixing, after a couple days in the fridge, and even after a couple hours coming up to RT before opening.  I am trying to remember if the poolish had collapsed on that batch.  I may have intentionally let it go to get more "yeasty" flavor in the dough.   (They all seem to blend together at this point!) 

Differences in temperatures (room temperature, ingredients temperature...) and in yeast quality (even within the same bag) can bring differences from a fermentation to another. If the poolish is overfermented it's possible that a part of the yeast already became inactive/dead. But that's one of the advantages of these pre-ferments, even if it is in bad shape we're only talking about half the dough, and we'll have a brand new half soon that will heal everything 

My two examples are why I asked the question about whether an over-fermented poolish is dead-dead, or whether is is just dormant, and will be revived when given more flour in the final dough.  Your reply would suggest the former, that a over-fermented poolish will be less active, and that some added yeast in the final dough may be needed, at least to avoid having to wait forever to get some rise.  Right?

This makes me now question my assertion that always adding extra yeast is the right thing to do as "insurance".  Better I be more deliberate and attentive to the state of the poolish, and only add more yeast if I suspect that it is either under- or over-fermented.  Would you agree with this?

Thanks all for replying!         

[Pete-zza]

Don,

I often cite the following articles on preferments by Didier Rosada, an acknowledged expert on dough, including preferments like poolish but also preferments like sponge, biga and prefermented (old) dough. I found the articles when I was trying to learn all about preferments. The two articles were my go-to articles when I made preferments. Didier once worked at the San Francisco Baking Institute but later went into the commercial side of the business. Here are the articles:

http://web.archive.org/web/20040814193817/cafemeetingplace.com/archives/food3_apr2004.htm, and

http://web.archive.org/web/20050829015510/www.cafemeetingplace.com/archives/food4_dec2004.htm.

Unfortunately, in the case of poolish, the articles do not show what the poolish should look like at various stages. The original articles contained photos to show this but once the articles were no longer available those photos were no longer available. What I cited comes from the archives of the Wayback Machine that preserved the original articles sans the photos. But if you follow the "rules" for poolish, you should be in good shape. You will also read what happens when a poolish is past its prime.

I also searched my posts today to find a photo that shows when a poolish is ready to use. I found such a post. See the first photo in the post at Reply 17 at:

https://www.pizzamaking.com/forum/index.php?topic=7225.msg76431#msg76431

To the above, I should add that the Rosada articles are in the context of bread making but the basic principles also apply to doughs using preferments like poolish. My citation is intended to be educational while still being relevant.

I also played around with sourdoughs but my advice is not to go initially to sourdoughs. Actually, I place sourdough at the bottom of the list for beginners. My advice for beginners is to play around with cold fermented doughs first, followed by room temperature fermented doughs, commercially leavened preferments (like poolish), and, finally, sourdoughs.

You might also find it useful to look at the many definitions concerning preferments that are included in the forum's Pizza Making Glossary, at:

https://www.pizzamaking.com/glossary.html

In fact, if you read the entire Pizza Making Glossary, you will know more about pizza than just about the entire population in this country .

Peter

[donstavely]

Thanks Peter.  I actually had read these preferment articles a while back in another post (probably by you.)  I didn't know then as much as I do now, so a gleaned a lot more reading it again.  Same is true about the glossary.  Funny how hard it is to learn everything all at once! 

[PizzaPassion]

Interesting to read this regarding yeast after using a starter as I just had this identical issue in the past two weeks. For perspective I am not a professional by any stretch and much of what I have learned is from the Pizza Bible with some help from forum members Scott, Craig and Peter along the way. In any event I made my best ever pizza two weeks ago using Tony's Master Dough with Tiga Starter but had reduced the ADY yeast to 1/4 tsp. My particular recipe uses 300 grams of flour so if my math is correct that equates to .24% of yeast. Tony's recipe calls for .5% or twice as much yeast. Well this past week we had some friends over for pizza so I doubled the recipe but I also deferred to the .5% yeast called for in the Pizza Bible. My dough was tough, chewy and heavy. The lightness and airy texture were gone. The extra yeast which felt like a safety net had proven to be just the opposite. My great dough from two weeks earlier was, IMO, pretty average but acceptable pizza dough.
So my takeaway, as an amateur, is sometimes less is more especially when it comes to yeast.

[Yael]

[...]
My two examples are why I asked the question about whether an over-fermented poolish is dead-dead, or whether is is just dormant, and will be revived when given more flour in the final dough.  Your reply would suggest the former, that a over-fermented poolish will be less active, and that some added yeast in the final dough may be needed, at least to avoid having to wait forever to get some rise.  Right?
[...]   

Yes exactly. It's just simple math as yeast amount is limited and has limited resources.

[...]
This makes me now question my assertion that always adding extra yeast is the right thing to do as "insurance".  Better I be more deliberate and attentive to the state of the poolish, and only add more yeast if I suspect that it is either under- or over-fermented.  Would you agree with this?

Thanks all for replying!       

In general or in theory yes, however in practice it will not be so complicated. Well maybe during the first tests only. The longer the poolish (meaning with a little amount of yeast), the longer the range of use, so these problems will certainly be minimal. BUT, the longer the poolish, the longer the following fermentation if no yeast added. So it's really up to what you're looking for.

[robertofrog01]

So I have been trying to figure out exactly the same questions as Don.

I want to incorporate a Poolish for flavour, but what on earth does that say about how much yeast will be going into my final mix?  Do I need to add any more?  How much Poolish should I use?  What yeast do I calculate in my final fermentation?

With assistance from the new Bing AI, I found this article..
https://www.thespruceeats.com/bread-making-yeast-faq-1447197
Which contains this text:
"One gram of yeast contains 20 billion tiny cells. There are about 7 grams in a quarter ounce package that we buy at the store (2 1/2 teaspoons). That's 140 billion cells! When you start making bread, add the amount of yeast called for in the recipe. If it tastes good and has the properties you want, then stick with it. Because yeast does not divide much in bread dough (only 20-30% increase in cell numbers in 4 hours), what you start with is what you end up with in terms of yeast numbers."

So my assumption is that unless I let the Poolish yeast start to die by over-fermenting or keeping it more than 24hrs, I'll have 1.2x as much yeast going into my mix as I put in my Poolish.

I know there's an art to this stuff, but I'm on a mission to design my perfect dough method and I want to use science as much as possible to achieve results with rock-solid consistency if possible.

[Anton1]

I want to incorporate a Poolish for flavour, but what on earth does that say about how much yeast will be going into my final mix?  Do I need to add any more?  How much Poolish should I use?  What yeast do I calculate in my final fermentation?

Here's an example from BBGA using yeast in the poolish plus a levain plus yeast in the final dough.

[TXCraig1]

I don't think I've ever added any additional yeast when incorporating the poolish into the final dough.

[scott r]

Just like dealing with direct doughs, it really comes down to when you want your dough to be ready and how you are fermenting.  Of course there is also the variable of how much poolish you are using in your final dough. 

If you do an 18 hour room temp poolish there is very little yeast in it.  In this situation you are more than likely going to want to add some additional yeast when mix time comes.   

If you are doing a fridge fermented poolish in a fairly short amount of time (many do this over night for instance) you are going to need a lot of yeast up front in the poolish and you more than likely will not want any more at mix time.