I have set forth below a dough formulation for you to consider that makes use of a sponge preferment. That formulation is a conversion of the dough formulation as set forth in Reply 1805 at http://www.pizzamaking.com/forum/index.php?topic=9068.msg304434#msg304434
to a sponge format.
As you can see, I was able to use the preferment dough calculating tool at http://www.pizzamaking.com/preferment_calculator.html
to come up with the formulation. However, it took a lot of playing around with the output of the formulation to include the IDY in the sponge Preferment and to adjust the IDY in the Final Dough (as shown below) and to get all of the numbers to line up. In retrospect, it would have been far easier to leave out the IDY component of the sponge Preferment, like Walter did, and to simply state what the amounts of IDY should be in the sponge Preferment and in the Final Dough. However, I wanted you to see exactly how all of the numbers look so that you can make similar adjustments at a later date should the formulation presented below be useful but still need adjustment. Unfortunately, there is no easy way of getting around the need to do a fair amount of math calculations whenever basic variables are changed, whether it is the amount of the sponge Preferment, the temperature of the prefermentation, or the duration of the prefermentation period, or any combination thereof.
As background, I used the following assumptions:
1. The dough batch is enough to make five dough balls, each weighing 1.15 pounds (18.4 ounces), for a total of 92 ounces.
2. The bowl residue compensation is 2%. For scaling purposes, 18.4 ounces should be used for each of the five dough balls.
3. The room temperature during the prefermentation of the sponge Preferment is 68 degrees F.
4. The duration of the prefermentation of the sponge Preferment is 20 hours.
5. The temperature of the water used to make the sponge Preferment is 60 degrees F (per Didier Rosada).
6. The sponge Preferment is 65% of the total formula water of 1000.02 grams (based on Rosada).
7. The hydration of the sponge Preferment is 63%, which is the same as for the dough formulation given in Reply 1805 cited above.
8. The sponge Preferment percent of water is 38.6503% (this number is used in the preferment dough calculating tool).
9. The thickness factor that corresponds to a 16.5” pizza using 18.4 ounces of dough is 18.4/(3.14159 x 8.25 x 8.25) = 0.08605.
10. The flour used is the Full Strength flour, the salt is Morton’s Kosher salt, and the oil is the Lira Olive Pomace Oil.
11. Upon completion of the Final Dough and dividing and scaling, the dough balls will be subjected to a period of cold fermentation.
You will note that, as Walter has stated, there is not much yeast (IDY) used in the sponge Preferment. It comes to 1/16 teaspoon of IDY. That is convenient because it is a standard mini-measuring spoon that is called “pinch”. The amount of IDY to use in the Final Dough is also a convenient value. It is a bit more than 1 ¼ teaspoon.
You will also note the 63% hydration of the sponge Preferment. That should yield a texture like the Final Dough into which it is to be incorporated but there may be some slight differences to the extent that some of the water in the sponge Preferment evaporates during the period of prefermentation. Also, the Final Dough contains some oil that might lead to slight differences in extensibility.
Within the framework of sponge preferments as described by Didier Rosada, there are a myriad of possible combinations. But, even within the Rosada constraints, there would not be a lot of yeast in the sponge Preferment for the duration of the prefermentation you would be using and also the temperature of prefermentation that you would be using. I used member November’s analytical approach to adjust the Rosada prefermentation profile as set forth in the Rosada article referenced earlier in this thread to fit your particular situation.
Here is the formulation:Total Formula
Flour (100%): 1587.33 g | 55.99 oz | 3.5 lbs
Water (63%): 1000.02 g | 35.27 oz | 2.2 lbs
Salt (2%): 31.75 g | 1.12 oz | 0.07 lbs | 6.61 tsp | 2.2 tbsp
IDY (0.25%): 3.97 g | 0.14 oz | 0.01 lbs | 1.32 tsp | 0.44 tbsp
Oil (1.5%): 23.81 g | 0.84 oz | 0.05 lbs | 5.29 tsp | 1.76 tbsp
Sugar (0.85%): 13.49 g | 0.48 oz | 0.03 lbs | 3.38 tsp | 1.13 tbsp
Total (167.6%): 2660.36 g | 93.84 oz | 5.87 lbs | TF = N/A Preferment
Flour: 398.78 g | 14.07 oz | 0.88 lbs
Water: 251.23 g | 8.86 oz | 0.55 lbs
IDY: 0.19 g l 0.0067 oz l 0.063 tsp (1/16 tsp "pinch" mini-measuring spoon)
Total: 650.2 g | 22.94 oz | 1.43 lbsFinal Dough
Flour: 1188.55 g | 41.92 oz | 2.62 lbs
Water: 748.79 g | 26.41 oz | 1.65 lbs
Salt: 31.75 g | 1.12 oz | 0.07 lbs | 6.61 tsp | 2.2 tbsp
IDY: 3.78 g | 0.13 oz | 0.01 | 1.26 tsp | 0.42 tbsp
Preferment: 650.2 g | 22.94 oz | 1.43 lbs
Oil: 23.81 g | 0.84 oz | 0.05 lbs | 5.29 tsp | 1.76 tbsp
Sugar: 13.49 g | 0.48 oz | 0.03 lbs | 3.38 tsp | 1.13 tbsp
Total: 2660.36 g | 93.84 oz | 5.87 lbs | TF = N/A