Incorporating Poolish into Dough

[Tbombs34]

I am thinking about trying a poolish for the first time this weekend.  I've read up on the use of preferments on the forum and elsewhere and have a decent idea of how to get a poolish started.  It's my understanding that you basically combine equal parts water and flour with a small amount of yeast and let it ferment at room temperature for 8-12 hours, depending on the amount of yeast used, the temperature of the water used and the room temperature.  If my understanding is incorrect or incomplete, please let me know.

I have a few questions  :

1) How do I know how much flour, water and yeast to use?  Should the total poolish weight be a certain percentage of the desired dough ball weight (taking into account the desired hydration level)? 

2) Is the yeast used in the poolish measured as a percentage of the flour used in the poolish or as a percentage of the total flour weight?

3) When ready to use the poolish, do I just add the remaining ingredients to the poolish and proceed with my dough making process?

Thanks for the help!

[Pete-zza]

Tboms34,

Your understanding of the poolish is essentially correct. However, it is possible to make poolish with a prefermentation period of from 3 hours to 15 hours or more. Of course, the shorter duration poolish would use more yeast than a longer duration poolish.

With respect to your specific questions, here is my response, using your numbering system.

1) and 2). In the bread world, where poolish originated, it is common to use 20-80% of the formula water as the weight of the poolish, although some bakers will use poolish as a percent of the formula flour or even the total dough weight. The 20-80% water range is the range that Didier Rosata, formerly of the San Francisco Baking Institute, recommends. The more poolish you use, the more acids and other byproducts of fermentation you will get, which will contribute to crust color, flavor, aroma and texture of the finished crust, but at the expense of a more elastic gluten mesh (stronger dough) and a higher risk of sugar depletion (the natural fermentiscible sugars extracted from the flour by enzyme performance). This means that you may have to add some sugar or diastatic malt (about 0.5-1% of the total formula flour) as part of the final mix. Otherwise, a nice brown crust coloration in the finished crust may be lacking.

The amount of yeast to use in the poolish is as a percent of the poolish flour, not the total formula flour. Typical prefermentation/yeast profiles, also from Didier Rosata, are as follows:

3 hours: 1.5% fresh yeast, as a percent of poolish flour
7-8 hours: 0.7% fresh yeast, as a percent of poolish flour
12-15 hours: 0.1% fresh yeast, as a percent of poolish flour
Note: Prefermentation assumes a room temperature of 80-85 degrees F, with water temperature = 60 degrees F

Either ADY or IDY can be used in lieu of fresh yeast. For ADY, use one-half the weight (or percent) of the fresh yeast; for IDY, use 40% of the weight (or percent) of the fresh yeast. If a different prefermentation temperature is used, or a different water temperature is used (e.g., to shorten or lengthen the prefermentation time), adjustment to yeast quantity will be required to achieve comparable results.

3) You simply combine the poolish with the remaining ingredients as part of the final mix. However, you want to wait for the break point (the point at which the top of the poolish collapses into itself and then recedes), or a short period thereafter, before conducting the final mix. If an autolyse is used (the classic autolyse), the poolish should be added after the autloyse rest period, to avoid incorporating any yeast into the dough and acidifying it during the autolyse rest period. Depending on the amount of poolish used and its temperature at the time of the final mix, it may be necessary to adjust the temperature of the remaining formula water to achieve the desired finished dough temperature (around 75-80 degrees F for a typical home application).

It usually takes a series of tests to determine the best amount of poolish and the best prefermentation time to use to achieve the desired end results.

For a recent example where I used the poolish method, see Reply 17 at http://www.pizzamaking.com/forum/index.php/topic,7225.msg76431.html#msg76431

Good luck, and please let us know how things turn out.

Peter

[Tbombs34]

Thanks Pete for your, as always, helpful and detailed answer.  You state that "it is common to use 20-80% of the formula water as the weight of the poolish."  Does this mean that I would then reduce my formula water by the amount of poolish used?  For example, if my formulation calls for 200 grams of water, I would use a poolish weight of 80 grams (assuming I am shooting for a poolish weight of 40% of the total formula water).  Would I then reduce the total formula water by 80 grams to take the poolish into account?  I would guess no, as this would mess up the hydration level. 

If I am going to use 80 grams of poolish, as described in the example above, that would also mess up the hydration level if I did not adjust the total formula water amount. 

Does the preferment dough calculating tool take this all into account?  If so, one thing I notice about this tool is that it has you add the yeast to the formula rather than to the poolish.  Assuming I want to add the yeast to the poolish, would I just add it all and then add none when mixing the dough?

Whew!!  Sorry for all of the questions, but the use of preferments is new to me and a little confusing.  Thanks all!

[Pete-zza]

Tbombs34,

Unfortunately, the preferment dough calculating tool (at http://www.pizzamaking.com/preferment_calculator.html) doesn't work for preferments like poolish. It is intended only for naturally leavened doughs using natural starters in small or preferment quantities and, if desired, supplemented with commercial yeast. When I was originally doing the design of the preferment dough calculating tool, I spent countless hours trying to see if I could also make it work with more traditional types of preferments--not only poolish but also bigas, sponges, prefermented/old dough, etc. However, because of the large numbers of possible combinations of ingredients that you will typically find in recipes, and the seemingly endless ways they can be split between the preferments and the final mix (in many cases, they are bastardized combinations that defy logic), I came to the conclusion that it was impractical to try to make the preferment dough calculating tool take on the added tasks of handling the more traditional forms of preferments. Consequently, when I work with poolish and similar preferments, I just drag out my calculator and go through the math, just as I did when I made the dough described at Reply 17 at http://www.pizzamaking.com/forum/index.php/topic,7225.msg76431.html#msg76431.

In your example, if your basic dough formulation calls for 200 grams of formula water and you want to use poolish at 40% of the formula water, that is 80 grams, just as you mentioned. Since the poolish is elaborated by equal weights of flour and water, this means that you will have to reduce the formula water (in the final mix) by 40 grams, not 80 grams. So, 200-40 = 160 grams of water will go into the final mix, along with the rest of the flour (the part not used in the poolish), possibly (and usually) more yeast, salt, and any other ingredients, like sugar and oil.

Some people add all of the formula yeast to the poolish. This is typically a bastardization of the classic poolish but can in some cases still produce acceptable results if other adjustments are made to the formulation and preparation. Other people split the formula yeast between the poolish and the final mix. The ratios can vary all over the place. If I am concerned that the yeast performance is likely to be adversely affected by a poolish with large amounts of yeast and a long fermentation time, I would include more yeast as part of the final mix, quite possibly with some sugar or diastatic malt.

It takes a fair amount of knowledge about preferments and working with them to be able to take an existing dough formulation and to convert it to a particular preferment version. It is because preferments and their use are biochemical activities, and each step has its own effect on the biochemistry of the dough, its development, and the end results. Sometimes, the easiest route is to piggyback on preferment-based recipes that have been demonstrated to work well and produce good results. For example, one of the most popular preferment recipes on the forum is JerryMac's NY style dough recipe at http://www.pizzamaking.com/forum/index.php/topic,5851.0.html. Jerry's preferment is not technically a poolish in the classic sense but I essentially modified it to be so at this thread: http://www.pizzamaking.com/forum/index.php/topic,6515.0.html.

Peter