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How to convert a yeast recipe to a Poolish ?

flynnboy's picture
flynnboy

How to convert a yeast recipe to a Poolish ?

Hi,

As a beginner to anything other than basic yeast bread recipes I am trying to get to grips with Poolish. In an effort to do this I am wondering if anyone can advise me on how I would convert a yeast bread recipe to Poolish ? For example, if I have a recipe as follows, how would I convert it to a Poolish recipe ?

500 grams Flour

1 tablespoon Salt

60 ml Olive Oil

20 grams Yeast (natural)

270 ml water

Thanks very much for any advice !

gavinc's picture
gavinc

Hi,

The answer to this is in the table I gave you yesterday on another post. If you check the table, I have taken 33% of the total flour for the poolish and he same weight of water. A small amount of the yeast included. The final dough mix is all the remaining ingredients from the total formula plus all of the poolish.

Cheers,

Gavin 

flynnboy's picture
flynnboy

Thanks Gavin,

Is this a universally recognised conversion formula, or your own ? What about the Olive Oil ?

Thanks very much, again, and excuse my ignorance.

gavinc's picture
gavinc

It is Hamelman's baguette formula and can be used for a loaf. Just add the olive oil during the final mix.  I don't recommend using volume measurements with the salt. I encourage you to ask any questions you need; there's no such thing as a silly question here.

flynnboy's picture
flynnboy

Thanks again.

flynnboy's picture
flynnboy

Thanks again.

Abe's picture
Abe

Although for your recipe 270g flour would be max for a poolish. What is 20g natural yeast in your recipe? Do you mean fresh yeast? 

My rule of thumb, when using fresh yeast aka cake yeast, is 1% of however much flour you're pre-fermenting. Then the remainder goes into the final dough. So take your recipe...

  • 500 grams Flour
  • 1 tablespoon Salt [That's a lot! - 2 tsp more like it]
  • 60 ml Olive Oil [also quite high]
  • 20 grams fresh yeast [cake yeast]?
  • 270 ml water [very low hydration]

For the sake of converting your recipe i'll keep it as it is for the sake of the conversion only. 

Now lets say 200g of the flour is pre-fermented in the poolish:

Poolish: 

  • 200g flour
  • 200g water
  • 2g fresh yeast

Final Dough: 

  • 300g flour
  • 1 tablespoon salt 
  • 60 ml Olive Oil
  • 18g Yeast
  • 70 ml Water
  • All of Poolish [200g flour + 200g water + 2g yeast]

 Although i'm not sure about the original recipe you can see how to calculate and convert it to a poolish recipe. 

  1. Since a poolish is generally 100% hydration then however much water is in the recipe that is the maximum of flour you can pre-ferment. Generally it is a good idea to not pre-ferment more than 50% of the total flour but as always it's not written in stone. 
  2. 1% of per-fermented flour for fresh, or cake yeast, and 1/3rd of that if using IDY. 
  3. The remainder of the yeast goes into the final dough
flynnboy's picture
flynnboy

Thank you very much Abe ! BTW that is a basic white bread recipe from the celebrated Baker Paul Hollywood !?

Your yeast weight seems high compared to what I have read elsewhere ?

I appreciate the recipe !

Thanks again.

Abe's picture
Abe

If the yeast you're talking about is Fresh Yeast the 1% of however much flour one is pre-fermenting is fine. 

Perhaps recipes you have seen elsewhere are using Instant Dried Yeast in which case one would use 1/3rd of that. 

So in our case, when pre-fermenting 200g of flour, then instead of using 2g fresh yeast one would use 0.7g IDY. 

flynnboy's picture
flynnboy

Thanks again Abe. In fact I am no longer a fan of Hollywood, I have never made a successful loaf from his book, which I think he has skipped on with detailed instructions simply to sell his book on the back of his 'celebrity'

Yes I was talking about 'fresh' yeast and the recipes I have been reading about use IDY.

THANKS

Abe's picture
Abe

Take a very simple recipe...

  • 500g bread flour
  • 300g water
  • 10g salt
  • 1 teaspoon IDY
  1. Form dough.
  2. Knead till full gluten formation.
  3. Bulk Ferment till doubled. 
  4. Shape and final proof till ready. 
  5. Bake. 

Once you've done that then convert it into a poolish recipe. Like so...

Poolish:

  • 200g bread flour
  • 200g water
  • 0.7g IDY (a pinch)

Final dough:

  • 300g bread flour
  • 100g water
  • 10g salt
  • Rest of the IDY (1 teaspoon less 1 pinch)
  • All of the poolish

Then compare the results. 

flynnboy's picture
flynnboy

Thanks again Abe.

mariana's picture
mariana

Flynn, normally, one would use poolish to shorten bulk fermentation. In the recipe that you quoted bulk fermentation proceeds so fast (due to the enormous amount of yeast), under one hour at 25-27C, that poolish is hardly necessary. Of course, you can still prepare it, just for the sake of flavor, but it will not further shorten your bulk fermentation time. 

I've been using this recipe for bread daily in the last month or so, although I had no idea that it was 'Paul Hollywood's". It was from a book on bread machine breads, titled as a basic white loaf. It is very good with any amount of oil or butter from 1tsp per loaf to 40g or even 60g of oil. Paul Hollywood usually uses 40g of butter or oil in dough and 20 g or so to grease the kneading surface and the surface of the bowl where the dough bulk ferments. 

Anyways, the recipe for poolish depends on when you need it, when you are planning to mix your final bread dough. If you need it in 8 hours, then you use 0. to 1% of yeast in your poolish, if you need it in 12 hours, then 0.3-0.6%, if you need it in 16 hours, then 0.1-0.25% yeast, assuming you ferment it at 70-75F (21-24C).

Lower room temperature mean longer time to ripen or need for more yeast, at higher room temperatures your poolish will be ready sooner or would need less yeast to stay strong for a long time waiting to be used. For example, If you need it in 3 hours at 27-29C, then you use cool water (16C) and  1.5% yeast (to the amount of flour used in the poolish). The same poolish  will be ready in 16 hours at 80F (27C) with 0.08% yeast or it would need 0.25% yeast to be ready in 16 hours at 65F (18C). 

Traditionally, the size of a poolish has been calculated based on the water involved in the total formula. Bakers use from 20 to 80% of the total amount of water in the recipe to prepare a poolish, which is elaborated using the same amount of flour as water. This creates a hydration of 100 percent and provides a liquid consistency. The remaining yeast, water and flour in the formula would be used when mixing the final dough. 

You already own Jeffrey Hamelman's book 'Bread', all rules about conversion into poolish are on pages 88-89. 

Poolish is mixed in at the beginning of the mixing process even if autolyse is done, because its low yeast content won't really affect dough strength, i.e. you autolyse with the poolish in. 

Examples of a bloomer by Paul Hollywood's recipe (straight dough no poolish, 1-3 hours of bulk fermentation depending on how cold or warm is your room temperature) and by another baker (with a 12 hours poolish made at 18C and 2 hours bulk fermentation of the final dough also at 18C) are here

 

flynnboy's picture
flynnboy

Thanks Mariana.

One of the things that confuse me about Poolish is how on earth anyone can distinguish between something like 0.3 % IDY and 0.6% !?

Thanks very much for your input.

mariana's picture
mariana

Per kilogram of flour it's 3g and 6 g of instant yeast, Flynn. Or, in teaspoons, one tsp and two tsp of IDY.

Even if your poolish is just 1/4 of that amount, made from 250g of flour and 250g of water, it's 1/4 tsp and 1/2 tsp of instant yeast. In my set of measuring teaspoons, I have 1/8 tsp as well, so I could use them to make a poolish from 125g of flour (1 cup of flour).

Of course, I have a small scale that measures as little as 0.1g of yeast, so it's another way, but measuring traspoons are surprisingly precise as well.

Some people prefer to dissolve their yeast in water and use fractions of that liquid to measure small amounts of yeast. For example, 3 g (one level tsp) of instant yeast bloomed ("dissolved" by stirring the yest granules in water) in 100 g of water. Any fraction of 100g of that liquid will portion out for you the necessary small amounts of yeast for your poolish, if you bake only one small loaf and your poolish is small. 10g of it will contain 0.3g of IDY, for example. 10 g of liquid is two tsp.

Those who bake fresh homemade bread with poolish daily, simply prepare a larger batch of it in refrigerator and take out portions of it as needed for their daily baking needs. It keeps fairly well when refrigerated.