Wheat seed is received by the earth as it is preparing to hibernate. The shoots sprout slowly, feeling the warmth underneath the snow and preserving the evanescence of dreams as they grow. -GIANCARLO CONSONI, AUTHOR
In this chapter, we will look at a selection of breads made with yeasted pre-ferments. The benefits of using pre-ferments are undeniable, from the perspective of flavor, dough strength, keeping quality, and reduced production time (see Chapter 1, "The Bread-Making Process from Mixing through Baking," for a full explanation of the benefits of pre-ferments).
Before discussing the specifics of bread production, we will clarify the basic types of yeasted pre-ferments and explain their predominant characteristics.
Pâte fermentée, or simply "old dough," is just that: a piece of white-flour dough that is reserved after mixing and incorporated into the next batch of bread. Although the name is French, the practice exists wherever bread is made. (If your customers ask why your baguettes taste so good, you can probably charge an extra quarter if you tell them it's because you use pâte fermentée; telling them you put "old dough" into the mix just doesn't sound as good!) Aside from the flavor benefits of using some old dough in the new mix, it is obvious that using it is economically preferable to throwing it away. Of the major yeasted pre-ferments, this is the only one that contains salt.
Like other yeasted pre-ferments such as poolish and biga, pâte fermentée has a limited life expectancy, unlike natural sourdough cultures, which can be perpetuated for years. Refrigerated, pâte fermentée will last at most 48 hours before its leavening potential is expended. With ample freezer space, it can be frozen, although within a week the yeast spores in it will begin to die off and the pâte fermentée will suffer a loss of vigor. For the home baker who bakes once a week or so, freezing may be an option. The effort required to make a pâte fermentée the night before a bake day is minimal, however, and is justified by the superior bread that will result.
Poolish is a mixture of equal weights flour and water, with a very small portion of yeast added (in the .08 to 1 percent range, depending on how long the poolish will ripen before the final dough is mixed, and the temperature of the room in which the poolish will ripen). Being of equal weight in flour and water, it has 100 percent hydration-more like a batter than a dough. Salt is not included in poolish. Protease is an enzyme whose function is to denature protein, and in a loose mixture like poolish, protease activity is relatively high. It has the effect of increasing the extensibility of bread dough, which not only makes shaping easier (though perhaps harder during the early stages of hand-skill development), but also results in increased loaf volume. The aroma of a bowl of ripe poolish is intoxicating-sweet and nutty with a delicate hint of acidity-and the texture of the dough is beautifully silken, a true delight for the hands. As the name suggests, poolish is of Polish origin. Originally used in pastry production, it eventually found a place in bread making, and today is used by bakers around the world.
Biga is a generic Italian term for "pre-ferment." It can be stiff textured at 50 to 60 percent hydration, or it can be essentially the same as a poolish when made with 100 percent hydration and a small portion of yeast. In either case, there is no salt in a biga, just flour, water, and a bit of yeast. The yeast quantity is determined by ambient temperature, and by the length of time it will be left to ripen before the final dough is mixed. As with poolish, the yeast in a biga is generally in the .08 to 1 percent range.
Production Notes for the Formulas in This Chapter
Preparing the Pre-Ferment. The pre-ferment is made at least 6 hours or up to 16 hours before the final dough is mixed (pâte fermentée is usually an exception to this, as it is simply dough removed from the prior batch, but it too, of course, can be mixed on its own). The flour, water, and yeast are mixed for about 3 minutes on first speed. Gluten development is not the goal at this point, so first speed is all that is required. Be certain that all the flour has been hydrated, turn off the mixer, and cover the pre-ferment with plastic to prevent a crust from forming on the surface. The pre-ferment will ripen at room temperature.
Knowing the signs of ripeness is very important: When the poolish is ripe, the surface will be covered with small bubbles-in fact, you should see bubbles breaking through to the surface, indicating the continuing activity of the yeast. If there is evidence that the poolish has risen and then collapsed (you may see a "highwater" mark on the sides of the bowl), then the poolish is past its prime. A stiff-textured biga and a pâte fermentée are ripe when they have domed and are just beginning to recede in the center. The goal is to have the pre-ferment at its full ripeness when you are ready to use it, and therefore the correct yeast quantities will increase and decrease as the seasons come and go. The amount of yeast necessary for a poolish to ripen in 16 hours at 80°F might be .08 percent of the poolish flour weight, but the same poolish might need .25 percent yeast at 65°F. The other factor determining yeast quantity is the duration of the ripening phase, with longer ripenings needing less yeast. Below is a general guideline, based on a room temperature of 70° to 75°F: The percentage of yeast is based on the weight of the flour used in the pre-ferment, not the flour in the overall formula. The percentages given are for fresh yeast.
LENGTH OF RIPENING % YEAST Up to 8 hours .7 to 1% Up to 12 hours .3 to .6% Up to 16 hours .1 to .25%
When a portion of a fully mixed batch of bread is removed for use as pâte fermentée in a subsequent mix, this portion is fully yeasted, as is of course the rest of the dough from which it has been removed, and is therefore in a special category. If the pâte fermentée will not be used within about 6 hours, it must be refrigerated-if it stays at room temperature for too long, it will completely lose its vigor because it contains a full proportion of yeast. Let it stand at room temperature for an hour or so in order for it to begin fermenting, then degas and refrigerate it. It should be cooled as quickly as possible, and degassed once or twice more over the next few hours. When it is used in the new mix, its temperature must be accounted for when computing the correct water temperature for the final dough.
The amount of fresh yeast used in the pre-ferments for all the formulas in this chapter is .2 percent. This often amounts to little more than .1 ounce. Further, for the sake of consistency, the yeast in the pre-ferments is expressed in units of pounds and kilograms, even though this means there are weights like .007 kg or .013 lb, as in the Baguettes with Poolish formula. A review of kilogram-to-gram and pound-to-ounce conversions will be helpful here; let's do it using the Baguettes with Poolish formula (more metric-to-U.S. conversions are given in the Appendix on page 387). To convert kilograms to grams, multiply the portion of a kilogram by 1,000 (the .007 kg needed for the pre-ferment in the Baguettes with Poolish formula converts to .007 × 1,000 = 7 grams). To convert from pounds to ounces, multiply the portion of a pound by 16 (the .013 lb of yeast in the formula converts to .013 × 16 = .2 ounces). The biggest difficulty arises with the Home column: Since baking is not usually done in quantities that justify the use of fresh yeast for most home bakers, instant dry yeast is called for in the formulas. In the Home column of the Baguettes with Poolish formula, the amount of instant yeast needed for the poolish is .0067 ounces. Clearly, this can't be accurately scaled. The solution: Use a speck of instant yeast in the pre-ferment, pay careful attention to temperature and to time duration, and closely observe the signs of ripeness. If, for instance, the pre-ferment ripens in 10 hours and you had hoped it would need 16 hours, use a smaller speck or a cooler ripening temperature next time. And conversely, if you want to ripen the pre-ferment in 12 hours and it seems not to have budged after that time, your speck should be a bit bigger next time, or the ripening room warmer.
Preparing the Soaker. A few of the formulas in this chapter use soakers. The soaking makes hard grains palatable, reduces their tendency to break the developing gluten network during mixing, and also reduces their tendency to "rob" moisture from the dough once it has finished mixing. Cold soakers are made by simply pouring water over the grains, mixing everything together, and covering the container with plastic to prevent evaporation. Hot soakers are made when any of the soaker grains are particularly hard and won't soften sufficiently in cold water (for example, cracked wheat and millet). In this case, bring the water to the boil and pour it over the grains. Stir and cover, as for a cold soaker. Salt is sometimes incorporated into the soaker in order to lessen enzymatic activity that might otherwise develop, with the potential of bringing some off flavors to the soaker. It's easiest to make a soaker when the pre-ferment is mixed. Both can then be left at room temperature until the time of the final mix.
Mixing the Final Dough. All the ingredients are placed in the mixing bowl. (There are some exceptions, for instance when ingredients like raisins or nuts are part of the formula; these are added at the end of the mix. Another exception is when dough is mixed using the autolyse technique. In that case, the salt and pâte fermentée, if used, are not incorporated at the beginning of the mix. There is a full discussion of the autolyse technique on page 9.) If using a spiral mixer, mix on first speed for about 3 minutes to thoroughly incorporate the ingredients (mixing guidelines for other kinds of mixers are given on page 11). Check the dough's hydration and make corrections as necessary, adding small amounts of water or flour as needed. (The formulas are balanced, but minor adjustments may be necessary; for instance, in very humid months it is a good practice to hold back a small portion of the dough water to compensate for the extra moisture held by the flour. It is best not to add flour if possible, since it would alter the overall proportion of salt in the formula.) It is also a good practice to taste for salt at this time to be certain it has not inadvertently been left out. Once satisfied that dough consistency is good, turn the mixer to second speed and mix for approximately 3 minutes, until a moderate gluten development has been achieved. Full gluten development in the mixer would mean overoxidizing the carotenoid pigments and loss of both the wheaty flavor of the flour and the creamy color we see in well-made breads. Rather than mixing fully, effective folding of the dough during bulk fermentation will complete the process of building dough strength, with no loss of color or flavor. There are a few exceptions to the 3-minute mix on second speed: First, when mixing doughs with soakers, another 30 to 60 seconds of mixing may be necessary, since the dough develops a bit more slowly in the presence of soaker grains; second, when using the autolyse technique, only 1 1/2 to 2 minutes of second-speed mixing will be necessary. The dough develops miraculously well during the autolyse, in spite of the lack of mechanical action, and surprisingly little time is needed on second speed to finish the mix. It will, in fact, break down rather quickly if overmixed. Since flour absorption rates can vary significantly from season to season and from mill run to mill run, and since soakers lose sometimes more and sometimes less water to evaporation, it isn't possible to be exact about water quantities in the formulas. It should be noted, however, that looser doughs tend to ferment better and have better volume and better flavor. For the most part, the doughs in this chapter should have a moderately loose feel to them. Each formula's hydration percentage will serve as a guide initially; your hands and experience will ultimately be the best guide.
Bulk Fermentation. Ripe pre-ferments contribute acidity to the finished mix, which in turn helps mature the dough and strengthen it. Bulk fermentation time can therefore be reduced. For the most part, 1 to 2 hours is long enough to fully mature the dough. As the percentage of pre-ferment increases, bulk fermentation time can be accordingly reduced. Some doughs, such as ciabatta, favor a lengthy bulk fermentation and seem to attain their fullest potential with as much as a 3-hour fermentation.
Folding is a fundamental requirement, and is a topic that is not without complexity. See page 15 for a full discussion of folding.
Dividing and Shaping. Breads like baguettes are typically divided into 12- to 16-ounce pieces, while other breads might weigh up to a few pounds. Once divided, all the doughs are preshaped round and left to relax, seams up, on a floured work surface, covered in plastic to prevent crust formation on the surface. Depending on the tightness of the preshaping and the nature of the individual dough, the pieces may need to relax from 10 to 30 minutes before the final shaping. For the most part, the breads in this chapter can be shaped round or oval (exceptions being breads like baguettes or ciabatta), and are suitable as well for pan loaves and rolls. The shaped breads take their final proofing in floured bannetons or between folds of baker's linen (or in loaf pans, as the case may be). Cover the loaves with baker's linen and plastic for the final proofing to prevent a surface skin from forming. When making rolls, proof them on sheet pans that have been sprinkled with coarse cornmeal or semolina, and later bake them on the sheet pans or directly on the hearth or baking stone.
Final Fermentation. For the most part, breads made with preferments need about 1 to 1 1/2 hours of final fermentation at 75°F. They should look well risen and feel light. Loading the breads when they are about 90 percent risen gives them the opportunity to spring proudly once exposed to the fierce heat of the oven.
Steaming and Baking. The proofed loaves are transferred to
the loading conveyor or baker's peel and placed with their seams
Excerpted from Bread by Jeffrey Hamelman Excerpted by permission.
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