User:Gandalf StormCrow/Draft: Techniques of Baking Yeast Breads
In its simplest form, Baking Yeast Bread is the process of baking a dough combining flour, water and yeast to make bread. Baking bread is elevated to art when the baker works to draw the full potential of substance and flavor out of grain to create a loaf that becomes "the staff of life." Classically, the bread-making process, from basic ingredients to finished loaf, is divided into twelve steps, though differences exist between the understandings of particular teachers and writers: organization, mixing, primary fermentation, degassing, dividing, rounding or pre-shaping, resting, final shaping, proofing, baking, cooling, and storing.
Classifications of Bread
Breads are classified in several ways, based on the ingredients or manner of preparation of the dough.
One system classifies bread based on the level of hydration of the dough. Stiff dough, such as for pretzels or bagels, has a hydration level of 50-57% of liquid to flour. Standard dough, such as for sandwich breads and many European-style breads, has a hydration level of 57-65%. And rustic dough, such as for ciabatta and focaccia, has a hydration level greater than 65%.
Another system classifies bread according to its richness. Lean dough, such as for French, many styles of sourdough, and bagels, has little or no fat or enrichments added. Enriched dough, such as for most sandwich breads and braided breads such as challah, has some fat or other enrichment added to the dough. And rich dough, such as for brioche and croissants, has a high degree of enrichment. A sub-category of rich dough is laminated dough, such as that for puff pastry and some types of biscuits, where the fat is layered in the dough by repeated folding.
Classifications according to manner of preparation include direct and indirect doughs. Direct doughs are those made with no preferments in one mixing cycle. Indirect doughs involve preferments and several mixing cycles.
The simplest dough can be made from flour, yeast and water, though the absence of salt yields a loaf tasting flat and dull to most modern palates. One line of variants of this simplest of recipes, however, has entered the pantheon of good bread: those from Tuscany. Tuscans overcome the flat taste by topping the bread with intensely flavored spreads and pastes or eating it with deeply flavored dishes.
What the French call pain ordinaire, which can be translated into English as ordinary bread, or the usual bread, includes only four ingredients: flour, salt, yeast and water. The flavor of any particular loaf of pain ordinaire must be coaxed out of the dough through the various techniques, both ancient and modern, available to the baker.
Bread dough also can be enhanced with additional ingredients. Sugars give a sweeter taste to the palate and provide an additional source of nutrients on which the yeast can work. Fats, in forms such as butter, shortening, oil or eggs, tenderize the dough, increase the richness of the dough and lengthen the bread's shelf life. Milk can be substituted for part or all of the liquid, which will tenderize the dough and darken the crust slightly, through the addition of lactose, which helps caramalize the crust. Seeds, herbs and spices, and other inclusions such as onions, garlic or roasted red peppers, add additional flavors to the dough.
Mixing the dough has three purposes: evenly distributing the ingredients throughout the dough, developing gluten and intiating fermentation. In creating a direct dough, all the ingredients are mixed together at one time, put through a single cycle of fermentation, then baked. An indirect dough, which can be used to coax flavor out of the dough by increasing the time of fermentation and enzymatic activity, is created by mixing the ingredients in several stages, with each stage undergoing a time of fermentation or enzymatic activity.
A mixing technique created by Raymond Calvel, the renowned French bread-baking professor, involves mixing only briefly the flour and water, and then letting the mixture sit for 20 minutes. During this autolyse phase, the protein molecules of the flour become hydrated evenly and gluten formation occurs in more complex and stronger ways than in the traditional mixing methods. Because the overall time of mixing and kneading is shortened, mixing which includes an autolyse phase are less oxygenated. The bleaching and changes in flavor caused by oxygenation are considered by many to be undesireable.
There are four types of pre-ferments commonly used, two "wet" types and two "dry" types.
Pâte fermentée, "old dough," is either a piece of dough reserved for use with the next batch of bread, or one made specifically to be used later. It is often used to enhance simple lean breads. Biga is an Italian term for "pre-ferment." It is made with flour, water and a bit of yeast. When made as a dry pre-ferment, it differs from a pâte fermentée only in its lack of salt. When made as a wet pre-ferment, it is essentially the same as poolish.
Poolish is a pre-ferment usually made with equal portions of flour and water and a very small amount of yeast. A sponge is a wet pre-ferment which includes most or all of the yeast. This shortens the length of time needed to finish the bread, but with less flavor improvement.
A final technique used in creating indirect doughs is to soak whole or cracked grains and seeds prior to their addition into the dough. This technique hydrates the grains or seeds so they don't rob the dough of water, softens them to lessen their ability to puncture the dough structure, and enhances flavor by lengthening enzymatic activity.
The initial mixing of ingredients yields a lump of dough that is coarse textured or mealy, and sticky. Kneading the dough—whether working the dough in a two-handed press-roll-turn manner, a slap-stretch-fold process, or some other method—transforms the initial lump into a finished ball of dough, lighter in color and less sticky with a satin-like texture. Many homebakers cherish the opportunity to knead their doughs by hand, gaining a sense of connection to the dough that is fulfilling. Some find spiritual benefits in handkneading, seeing the process as a pardigm for life. However, kneading can be also done with a breadmaker, a mixer, or food processor.
Fermentation and Proofing
All breads rise, some gaining volume before being put in the oven, while others get all of their rise through the time spent in the heat. Typically, yeast breads gain two thirds of their rise before being placed in the oven, and a third while in the oven. Quick breads may gain some volume from mixing or beating, but gain almost all of their rise in the oven.
Proofing is a step in creating yeast breads and baked goods where the yeast is allowed to leaven the dough. This step is not often explicitly named, and normally shows up in recipes as "Allow dough to rise".
During proofing, yeast converts glucose and other carbohydrates to carbon dioxide gas which gives the bread rise and alcohol which gives it flavor. Bacteria which coexists with the yeast consume this alcohol, producing lactic and acetic acids. Different types of bread have vastly different requirements for proofing depending on their recipe. Some breads will only require a single proofing while others will need multiple periods. Between stages of proofing recipes will often instruct a cook to "punch down" or "deflate" the dough to allow the bubbles of gas which have formed in the dough to deflate without popping (called overproofing). Length of proofing periods can be determined by time or characteristics. Often the "poke method" is used to determine if a bread has risen long enough; if the bread, when poked, springs back immediately it is underproofed and needs more time.
Proofing is divided into a number different categories including fermentation, proofing, retarding, autolyse. Fermenting is any stage of proofing which is completed prior to the shaping of the bread. Often a third of a bread's rise will occur during this stage. Proofing is the general term for allowing a break to rise while at room temperature after it has been shaped. Retarding is the stage in which bread is placed into a dough retarder, refrigerator, or other cold environment to slow the activity of the yeast. The retarding stage is rarely found in recipes with commercial yeast but often used in sourdough bread recipes to allow the bread to develop it characteristic flavor. Autolyse is a period of rest allowed for dough to relax. After the initial mixing of flour and water, the dough is allowed to sit. This rest period allows for better absorption of water and allows the gluten and starches to align. Breads made with autolysed dough are easier to form into shapes and have more volume and improved structure.
The dry heat of baking changes the structures of starches in the food and causes its outer surfaces to brown, giving it an attractive appearance and taste, while partially sealing in the food's moisture. The browning is caused by caramelization of sugars and the Maillard reaction. Moisture is never really entirely "sealed in," however; over time, an item being baked will become more and more dry. This is often an advantage, especially in situations where drying is the desired outcome, for example in drying herbs or in roasting certain types of vegetables. The most common baked item is bread. Variations in the ovens, ingredients and recipes used in the baking of bread result in the wide variety of breads produced around the world.
Over time baked goods become hard in a process known as going stale. This is not primarily due to moisture being lost from the baked products, but more a reorganization of the way in which the water and starch are associated over time, a process similar to recrystallization.
Bread baking equipment
To ensure consistent results, specialized tools are used to manipulate the speed and qualities of fermentation.
A dough proofer is a chamber used in baking that encourages fermentation of dough by yeast through warm temperatures and controlled humidity. The warm temperatures increase the activity of the yeast, resulting in increased carbon dioxide production and a higher, faster rise. Dough is typically allowed to rise in the proofer before baking.
A dough retarder is a refrigerator used to control the fermentation of yeast when proofing dough. Lowering the temperature of the dough produces a slower, longer rise with more varied fermentation products, resulting in more complex flavors. In particular, cold reduces the activity of the yeast relative to the lactobacilli, which produce flavoring products such as lactic acid and acetic acid.
A banneton is a type of basket used to provide structure for the sourdough breads during proofing. Proofing baskets are distinct from loaf pans in that the bread is normally removed from these baskets before baking. Traditionally these baskets are made out of wicker, but many modern proofing baskets are made out of silicone. Frequently a banneton will have a cloth liner to prevent dough from sticking to the sides of the basket. These baskets are used both to provide the loaf with shape and to wick moisture from the crust. Banneton baskets are also known as Brotform or proofing baskets. Alternatively, a couche or proofing cloth can be used to proof dough on or under. Couche are generally made of linen or other coarse material which the dough will not stick to and are left unwashed so as to let yeast and flour collect in them, aiding the proofing process.
A lamé is a double-sided blade used to slash the tops of bread loaves in artisan baking. A lamé is used to score (also called or slash or dock) bread just before the bread is placed in the oven. Often a lamé will have a slight curve to it which allows users to cut flaps (called shag) considerably thinner than would be possible with a traditional straight razor. This step allows bread to expand in the oven without tearing the skin or crust and also allows moisture to escape from the loaf. It also releases some of the gas, mainly carbon dioxide, trapped inside the dough. Proper scoring also allows the baker to control exactly where his or her breads will open or bloom. This significantly improves the appearance of baked breads. Scoring, finally create varieties in forms and appearance. It brings out the bread baker's artistic talent and marks his or her own signature.
- For more information on the classical understanding of the process of baking bread, see particularly Hamelman (2004, pp. 3ff) and Reinhart (2001, pp. 48ff). For one view of the art of bread baking, see the introductory chapters of Leader & Blahnik (1993), including the forward, written by Patricia Wells.
- Harold McGee (1984). On Food and Cooking: The Science and Lore of the Kitchen. Collier Books. ISBN 0-02-034621-2 (USA)
- Nancy Silverton (1996). Breads from the La Brea Bakery. Villard Books. ISBN 0-679-40907-6 (USA)
- Cook's Illustrated (2004). The New Best Recipe. America's Test Kitchen. ISBN 0-936184-74-4 (USA)