I found the folllowing guidelines for Poolish on the Internet:
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The Poolish
This method is composed of two phases. The first phase is the preparation of a semi-liquid dough comprised of yeast and an equal quantity of flour and water, which is prepared some hours prior to the preparation of the final dough. The second phase is the preparation of the final dough prior to baking.
The purpose of the preliminary phase is to allow for a rapid multiplication of yeasts, which leads to an increase in the strength and rising ability of the subsequent dough.
The percentage of yeast is based upon the amount of flour in the poolish, and varies according to the time in which the poolish is left to ferment. The following percentages are recommendations:
2.5% of yeast for 2 hours of fermentation at ambient temperature
1.5% of yeast for 3 hours
0.5% of yeast for 8 hours
0.1% of yeast for 12-16 hours
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It makes logical sense to me that the greater the time period, the less yeast would be needed.
What confuses me is that I am seeing a number for recipes with poolish which have a much greater percentage of yeast than these guidelines indicates, in relation to the time period. Examples are Floyd's Italian Bread and Hector's Cuban Bread (Hector doesn't call it poolish, he calls it starter, but it looks like a poolish to me. Both of these call for equal amounts of flour and water by volume, not by weight. I don't know what impact that has.
What is the effect of using relatively large amount of yeast and then letting it sit at room temperature for as much as 16 or 24 hours? Isn't there a point where that much fermentation has a negative effect?
Colin
One thought: I have seen recipes calling for poolishes that range between 75% and 125% hydration; they aren't always 100%.
sPh
There are a couple of pages in the BBA that seem to speak to this variation.
Firm/dry pre-ferment:
Biaga - made from scratch as a pre-ferment, no salt, as little as .5% yeast
Pate Fermentee - extra dough saved for leavening, contains salt
Wet pre-ferment:
Poolish - equal weights water and flour with .25% yeast, usually requires more yeast at final mix
Sponge - faster than a poolish, loads all or most of the yeast in the pre-ferment
So, the way I see it a Poolish is a specific type of wet pre-ferment and a sponge is another. Some fairly grey lines between the two for sure. Since Poolish is a term coined by the French bakers in honor of the techniques brought from Poland it seems to me that it is a specific way of making a sponge. Alas one person's sponge is another's poolish :)
From how I have used the terms used in BBA:
Poolish - a pre-ferment that is more hydrated (i.e., a higher percentage of water) than regular dough,
Pate Fermente - a pre-ferment with ingredients in the same percentages as the final dough, and
Biga - a pre-ferment that is less hydrated (a lower percentage of water or other liquid than the final dough).
However, that still leaves me wondering about the effect of high amounts of yeast in the Poolish.
Colin
just trying to learn something.
These are the relevant sections of the two recipes:
Hector's Cuban Bread
Starter (enough for two batches)
3/4 tsp yeast
1/3 cup warm water
1/3 cup all-purpose flour
Dissolve the yeast in the water in a NON-metallic bowl and let foam for a few minutes. Then add the flour and mix into a paste. Cover with plastic wrap and let mature for 24 hours.
Floyd's Italian Bread
Preferment:
1 cup water
1 cup bread or all-purpose unbleached flour
1/2 teaspoon instant yeast
To start the preferment, mix together the flour, water, and yeast in a small bowl and cover with plastic wrap. Leave out at room temperature for at least 4 hours and as long as 16 hours.
As for how much flour, I typically pre-ferment about 50% of the flour in a bread, but that's not the norm, perhaps because I almost always make 100% whole grain breads.
What I was taught about poolish is this (and I'm not saying it's right or wrong):
1) The purpose of the poolish is to ferment a portion of the flour, not to increase the yeast population (not enough oxygen there to get appreciable yeast reproduction). The less yeast used in the poolish, the more used in the final dough. I.e., amount of yeast in the overall formula is constant, whether you use less in the poolish and ferment it for longer, or more and ferment it for shorter.
2) The "right" amount of dry instant yeast relative to flour weight in the poolish, is (multiply by 2.5 to get % for fresh yeast):
3 hours:0.6%
7-8 hours: 0.28%
12 - 15 hours: .04%
The above has worked for me in my baking, but all of that said, theory is one thing and baking is a bit of another. Clearly Floyd and Hector have formulas that work, just because they do.
Susanfnp
http://www.wildyeastblog.com
.04% = .0004
So for 50g flour, .02 g yeast. Obviously 1/100 of a teaspoon is a little ridiculous to measure. Suffice it to say it's a really small amount!
Susanfnp
http://www.wildyeastblog.com
Last night, about 10 hours ago, I did two mixtures.
Each of them had 3/4ths cup water and 3/4ths cup bread flour. In one of them I mixed 1/4th tsp. yeast and on the other something less than 1/8th tsp. yeast. The temperature when I did this was between 75 and 80 F.
The one with 1/4th tsp. has crested and fallen back a little. The other one looks fully developed, but has not fallen back.
I will be going to work in a while and won't be back until the afternoon, and the forecast is for temps in the 80s today. I'm not sure at this point if I will put them in the refrigerator before I go to work.
Colin
[b]Gluttony[/b] - all things being equal, yeast finds it easier to absorb nutrients in a wetter environment (poolish) vs. a firm environment (biga or pate fermentee). Since yeast ain't got no legs, the subtle agitation of the poolish as gas bubbles rise will move individual yeast cells slightly, thus bringing them to new feeding pastures (so to speak).
[b]Sex[/b] - like many living things, yeast spends a great deal of time simply eating. However, yeast will reproduce (by budding) approximately every 2 hours if the conditions are right. (OK, it ain't really sex, but its all that a poor yeast organism has going for it.) Again, a poolish is a better environment for sex than a firmer dough. (Below, yeast organisms caught in the act...)
[b]Yeast[/b] - the above factoids apply to your friend and mine, Saccharomyces cerevisiae, aka commercial yeast. And possibly also to its wild cousins.
I think there is such a thing as too much fermentation in a poolish. When I've let mine go too long, it first gets hooch, then the gluten in the flour breaks down. I think if I were to use it in a dough, I'd get a slack one which would fall apart as there would be too much protease enzyme at work.
Incidentally, I made a batch of 9 grain bread a week ago. I poured the boiling water over the grains and added the recipe's salt, since it's very warm and I didn't want to have enzyme action in the mix. It took me longer to get to than I expected, and after about 16-20 hours of sitting at warm room temp, I finally made the dough. The mix still smelled fine and there were no crackly sounds either, which I believed indicated it was still okay to use. As the dough fermented, it fell apart into shreds. Evidently, there was something going on, and I believe, according to what I've read (thanks to PR and his new book!) that it was too much protease enzyme at work.
SOL
Italian Bread, More Yeast, Darker color
I am not sure how to get the captions next to the pictures properly.
Like my previous message said, I did two batches of poolish, one with 3/4 cup bread flour, 3/4 cup water, and 1/4th tsp. yeast. The other had the same flour and water but less than 1/8 tsp. yeast.
I started them at about 8 PM last night, looked at them this morning. The one with less yeast looked fully developed this morning and I put it in the refrigerator. The one with more yeast look past its prime, and I decided to go all the way and left it at room temperature until I got home around 2 PM. I made batches of Italian Bread using both batches of poolish, and just took them out of the over.
The one with more yeast, and the poolish looking past its prime made the better-looking rolls. I will taste them later this evening, and see if they taste differently.
I tried rolls from both batches last night, and both were good.
It looks to me like the process of making poolish, in terms of quantity of yeast and over-fermening, is very forgiving. If there is a line, I didn't cross it.
Colin
Can't you just hear that "crackle" of the crust? This loaf dissapeared fast.
Mini O
Hello, First of all, I am new here and this is my very first post. :)
Its interesting to see how the amount of yeast + time in a poolish can change the final product!(Mini oven's 300g loaf looks soo yummy)
I have a question about poolish and pre-ferments.
Can you add all the water from a recipe in a preferment along with half the yeast and flour?
So you are only left with adding the rest of yeast,flour, and salt the next day or however long you left the preferment.
Or! add ALL the water AND yeast(just like mini oven did) in a pre-ferment.
Is a very watery pre-ferment/poolish a bad thing?
Glad you like my little loaf. It was good. To answer your questions:
Can you add all the water from a recipe in a preferment along with half the yeast and flour?
Yes you can but it is handy if you split up the yeast, to split the water too, if only just a little bit to dissolve the second addition of yeast. If the poolish stands in a cool spot overnight, a little addition of warm (not hot) water can correct dough temperature and speed things up a bit. I do think I added some fresh water to my poolish to bring the weight up before adding salt and more flour.
Is a very watery pre-ferment/poolish a bad thing?
No, but I do like to add at least one third of the flour into a poolish so it is not really watery. I prefer my poolish to be a little more liquid than dough like because blending in additional ingredients is much easier.
Does that help? :)
Mini O
Thanks for the reply, that helped alot!
I just made a poolish for tomorrow, and this is actuatly my 2nd time making a poolish so it is farely new to me.
I am coping you and making a 300g bread : )
So this time I put 2/3 of the flour(200g all the wheat+some white bread flour) , about 300g of water, and 1/4 tsp yeast into the poolish ,I hope that works.
The common way is to have 1:1 ratio of flour and water (by weight). but I found it to be too thick. :/
I think i might have put too much water, I dont know.
Than mine. I had a total of 130g water. But that's ok, it will be about a 750g loaf. You will need an additional teaspoon of yeast when you mix your final dough and 1 1/2 teaspoons of salt plus 1 teaspoon of sugar. Bake for 30 to 35 min 220°c. or 430° F.
I often use 1:1 ratio, a lot depends on the flour, it does tend to loosen up overnight, and maths can be easier. It isn't a law, do whatever works for you. Honk if you need me, Mini :)
You are right MO! I needed to add LOT more flour, and I wish I did but...
This is what happens if I dont have a recipe. I am horible at following recipes. But more experience will make me better at making bread right!? so no biggie.
Anyways this is what it turned out to be like:
Very dense bread. I dont like the taste of whole wheat that much.. probobly because I dont know how to make a good one yet. This one was bitter and kinda sour.
Well, Putting on some jam made it some what edible :)
Mini Oven, Did your300g taste like a sour dough since you left it out for a long time??
It wasn't sour at all. I had 1 1/4 teaspoons yeast for my 300g of dough. Try it with just white flour first. 100g water, 100g flour and 1 teaspoon commercial yeast and let it stand room temp for 24 hours.
Mini O
If you don't like the bitterness of whole wheat, but want the whole grain, try white whole wheat. It's whole wheat flour made from white wheat, as opposed to red wheat. You should be able to find it anywhere that carries King Arthur flour - although Central Market is one store that doesn't carry it.
ps I can't resist improvising with my bread either, even though I'm not yet a good enough baker to get reliable results that way.
Next time, Ill try with thoes measurements, thank you MO!
Kippercat,
hmm White whole wheat. I never tried that. Im almost a health freak so Im sure I will be looking for that flour.