Table of Contents
- Mixing and Kneading
Bread is made by mixing flour and water into a dough, introducing a rising agent (historically, yeast), kneading the dough, and baking the dough. The Bakepedia site describes it:
Bread is a combination of flour and water that has been baked. Over the years, its production has become increasingly more complex with a multitude of additions ranging from fruit to nuts, and many different kinds of flours. Bread is a staple food in many countries, with cultural significance. With common sayings such as “the bread winner,” it has become one of the most important parts of the world’s diet.Bakerpedia.com, Specialties, Bread
Flour is the product of grinding and milling cereal (grain). The point of harvesting and milling grain is to preserve the starches, to be eaten and metabolized into glucose. When flour is mixed with water, starches dissolve. The starches are rearrranged by mixing flour with water, kneading dough and baking bread.
Grain and flour are NOVA class 1 unprocessed or mininally processed foods.
Unpackaged bread is a NOVA class 3 processed food, if
Processes include various preservation or cooking methods, and, in the case of breads and cheese, non-alcoholic fermentation. Most processed foods have two or three ingredients, and are recognizable as modified versions of Group 1 foods. They are edible by themselves or, more usually, in combination with other foods. The purpose of processing here is to increase the durability of Group 1 foods, or to modify or enhance their sensory qualities.https://world.openfoodfacts.org/nova
Packaged industrially baked bread is considered to be a NOVA class 4 ultraprocessed food due to the additives and the processing of ingredients:
Additives in ultra-processed foods include some also used in processed foods, such as preservatives, antioxidants and stabilizers. Classes of additives found only in ultra-processed products include those used to imitate or enhance the sensory qualities of foods or to disguise unpalatable aspects of the final product. These additives include dyes and other colours, colour stabilizers; flavours, flavour enhancers, non-sugar sweeteners; and processing aids such as carbonating, firming, bulking and anti-bulking, de-foaming, anti-caking and glazing agents, emulsifiers, sequestrants and humectants.
A multitude of sequences of processes is used to combine the usually many ingredients and to create the final product (hence ‘ultra-processed’). The processes include several with no domestic equivalents, such as hydrogenation and hydrolysation, extrusion and moulding, and pre-processing for frying.
The overall purpose of ultra-processing is to create branded, convenient (durable, ready to consume), attractive (hyper-palatable) and highly profitable (low-cost ingredients) food products designed to displace all other food groups. Ultra-processed food products are usually packaged attractively and marketed intensively.https://world.openfoodfacts.org/nova
Basic Technique and Science
Most people purchase bread made by industrial bakers from grocery stores. Some shop at bakeries.
Many people have kitchens and oven and could bake bread if they purchased flour and other ingredients and had time, and knowledge of technique and science. It isn’t rocket science but it is a specialized activity. Bread baking may have been a part of the education of students in home economics courses. Persons who work in bakeries may have taken courses in vocational educational institutions or learned from experienced bakers in work experience.
Publishers have published some texts and educational aids and many recipe books, but few books that can assist a beginner with basic technique. A useful book, in the Amazon Kindle store: Bread Science, by Emily Jane Buehler, published by Ms. Buehler, as Two Blue Books in 2006 and as a Kindle e-book in 2014, republished in 2021 in a 2nd edition. Ms. Buehler worked in a coop bakery, and taught community courses before she wrote this book. She researched the science of grain, milling, dough and baking in the professional journal collections of the University of North Carolina, Chapel Hill. She presents the science of gluten and fermentation, the practical technique of handling dough, an explanation of bakers’ percentage, and a discussion of the techniques of making and using preferments – sponges and starters.
YouTube has videos that demonstrate technique and what dough looks like as it is worked. Finding them is not easy, as search tools drive users to sift through many search returns.
Lesaffre’s Red Star brand has some useful videos on its channel:
- How to make yeast bread using the hand kneading method (2014);
- How to Make YEAST BREAD Using a STAND MIXER;
- How to Knead Yeast Bread Dough by Hand.
Flour Milling Standards
Whole wheat and bread flour weigh the same amount per unit of volume. Whole wheat flour, pastry flour and American all-purpose flour have proteins to make gluten but not quite enough. Bread flour milled to US and European standards (and Canadian All-Purpose) at 12.5% has more of the proteins that bond to form gluten. Gliadin and glutenin are insoluble proteins in grain and in flour. The proteins are found in wheat flour, and also can be extracted by milling, processed as vital wheat gluten (“VWG”) powder, and mixed into bread dough:
Consisting of mainly gliadin and glutenin, wheat gluten is unique among cereal proteins based on its ability to form a cohesive and viscoelastic mass. This rheological property makes it a dynamic material that is able to grow and keep the gasses within the dough during extended fermentation periods. The viscoelastic nature also provides the oven spring (increase in height due to the expansion of gasses) that we see in the oven.
The addition of VWG generally increases the dough mixing time and fermentation time. As more protein solids are added, more water is needed for complete flour hydration.
Due to its cohesive and viscoelastic properties, its main function is a dough strengthener. It is also a film former, binder, texturizer, fat emulsifying agent, processing aid, stabilizer, water absorption and retention agent, thermosetting agent, and a flavor and color binder.
Vital gluten can absorb almost twice its weight in water (140–180% water). The quality of dry vital gluten is estimated with the Brabender farinograph or Chopin Alveograph. The breadmaking quality of VWG is also assessed through standardized baking tests.Bakerpedia.com, Articles, Vital Wheat Gluten
When water is added to flour, these proteins bond into strands and sheets of gluten “a composite of storage proteins … found in wheat, barley, rye, oats, related species and hybrids … “. Gluten gives elasticity to dough, helping it keep its shape and often gives the final product a chewy texture. Gluten relaxes in time which lets the dough flow and rise.
Gluten forms when water is added to wheat flour. Bakers knead dough, stretching and folding it on itself, repeating the motion for several minutes. This structures the gluten. A baker can pause after mixing or start kneading, or pause during kneading. Kneading structures or pulls the gluten into a network of micro balloons. The dough should be viscous (tenacious and elastic) to hold together, but extensible to stretch, and to flow. A professional baker will probably use a mechanical mixer; many home bakers may have one. A mechanical mixer or stand mixer uses mixing arms, a paddle or a spiral dough hook in a circular or elleptical motion. A mixer has a range of speeds. The baker uses a slow speed to mix the ingredients and a higher speed to knead.
A rising agent (leavening) creates bubbles in the dough that create the bubbled texture of the “crumb” inside the crust of the baked loaf. Until chemical leavening agents were developed, bread was leavened by adding baker’s yeast. Yeast consumes some of the starches – it ferments, creating gas, which is trapped in gluten in the dough, which makes the bread rise, after the dough has been kneaded. Bakerpedia explains, condensing a number of complex biochemical processes:
When yeasted dough ferments rises and increases in volume, and flavor is developed. Yeast converts starch in flour into sugar, carbon dioxide and ethyl alcohol. CO2 gas is trapped by gluten proteins in the flour which causes dough to rise. Fermentation results in a light and airy crumb.Bakerpedia.com, Vital Wheat Gluten
The yeast propogates. Propogation and fermentation accelerate until the yeast cells run out of starch, or are killed off by high temperature. The dough rises in 2 or 3 stages: bulk fermentation, and intermediate and final proof. Dough is knocked or punched down to release gas at the end of the bulk fermentation, and folded when the loaf is shaped. The dough rises again in the baking pan and springs when yeast warms up after the pan goes in the hot oven, before the heat warms the dough and kills the yeast.
Commercial bakers use chemical leaveners for some bread. Home bakers use baking powder and baking soda for corn bread, soda bread, cakes and other baking. Baking powder is baking soda mixed with cream of tartar. Kraft Foods Magic Baking Powder does not provide Food Facts on the labels of small jars in Canada. The published information is that 1 tsp has 300 mg. of sodium. Substitutions for baking powder involve 1/4 tsp of baking soda plus some acid (e.g. vinegar, cream of tartar) for each tsp baking powder. Baking soda is sodium bicarbonate. It has 1,259 mg. of sodium per teaspoon, which explains the food facts for baking powder. The science of substitution for baking soda and baking powder is to use potassium bicarbonate, which is the key ingredient of Featheweight – not an widely available (i.e. in grocery stores) product. It is available as a supplement but has a list of side effects and do not use if taking medication warnings. Please Don’t Pass the Salt has recipes for quick breads, and suggestions on low sodium “baking mixes”. “Natural” products that that might trap CO2. Some recipes for some baked goods suggest that some natural products may trap CO₂ e.g. whipped egg whites.
Mark Kurlansky’s excellent book Salt: a World History (2002) tells of the use of salt to bake bread in Egypt (3,000 BCE), The production of salt may have started about 8,000 years ago. The right ratio of flour to salt and yeast, among other things, means a loaf that will rise on time, and not overproof or balloon. The loaf should spring in the oven and crown to form a dome.
Salt is part of the process for most bread sold by grocery stores and bakeries large and small. Bread is high in sodium, as an effect of the baking process.
Salt is a standard and necessary ingredient in most formulas and recipes. Salt:
- has a chemical effect on the taste buds (Lallamand Baking Update, Volume 2, No. 6);
- affects the development of gluten. It affects chemical bonds in amino acids in proteins in flour that has been exposed to mixed with water. It makes the gluten more tenacious and elastic;
- controls yeast which affects fermentation. Fermentation affects flavour but it also affects rise, which affects the size of the loaf and the production line.
A few bread styles, such as Tuscan bread, are made without salt.
Salt can be reduced, with a reduction in the amount of yeast. Some books and internet pages eliminating salt but incorrectly list the same amount of yeast that would be used if there was salt in the recipe! This will may bake or collapse. In a bread machine, the dough will balloon and may or collapse before it overflows the pan.
Every reduction in salt has to be balanced with a reduction of yeast. Please Don’t Pass the Salt has recipes for yeasted breads and a note on the general adjustment for yeasted bread recipes. Artisan bread baking writers suggest that adjusting the salt in formulas leads to unsatifactory results – e.g. Peter Reinhart, Artisan Bread Every Day (Ten Speed Press, 2009) at p. 15 suggests not reducing by more than 10%. Salt and kneading affect gluten. It is easy to get to reduce salt to 50% and 33% reduce the salt added to the mixing machine when dough is mixed. These reductions are difficult for industrial bakers. Changes in salt will affect the gluten, affecting texture, and storage of bread, as well as fermentation and taste.
The most precise way of measuring is by weight.
|Goal||Reduction||Use Salt||Use Yeast|
Mixing and Kneading
Modern professional bakers work with hundred of kilograms of flour and water. Professional bakers have control over how long to mix/knead, rise (ferment/proof), bake, and over oven temperature. Ingredients are mixed and kneaded in large industrial mixers, fermented, put into pans and put into ovens, baked, turned out and packaged. The dough goes into pans in small irregular lumps. It has to rise and flow to fill the pan, spring when pans go in the oven, but not spring above the limited headspace of the pan. Professional bakers may use 10-15 minutes of “intensive mixing” – the mechanical mixing of yeasted white flour dough was dominant in professional bakeries for French loaves until Raymond Calvel devised the hybid style in the 1960s. Intensive mixing develops gluten in white flour rapidly. Home bakers with stand mixers use slower speeds due to limitations of machinery (see the stand mixer review by America’s Test Kitchen in print and YouTube) or to use a hybrid, modified or improved mixing method. Overmixing is a risk for professional bakers using industrial mixers. Machine mixing can stretch dough too much or too often, breaking the gluten strands. An overmixed dough cannot hold the gases, and will not rise. Intensive mixing may affect a loaf with effects short of the complete failure caused by overmixing. Home bakers can have the same problem. A variety of mixers are available to the home baker:
- Food processors can mix dough, although a food processor might only handle 3 cups of flour, and has one speed – very fast. The mixing time may be less than a minute. Some food processors have a dough speed and/or special blade to mix dough. The risk of overmixing dough in a food processor is well recognized.
- A home stand mixer can handle several cups of flour, at low-medium speed settings. The power output of a Kitchen Aid stand mixer with a 5 quart bowl may be 325 watts. Larger stand mixers may output 800 watts. A Bosch Compact Kitchen Machine may output 400 watts into its dough hook in its stand mixer configuration. They have to be used at the right settings and for a short time.
Professional bakers and some home bakers express ingredient lists or recipes in baker’s percentage (B%) to use consistent processes to manufacture a consistent product. Professional bakers may use 2 pounds of salt and .77 pound of instant yeast per 100 pounds of flour. The B% for salt is 2%; the B% for instant yeast with most loaves made with bread flour is .7% but B% can vary. It may be over 1%. A yeast B% of .7% in one loaf works out to .3 ounces = 8.5 grams = 8,500 mg. salt per 3 cups (15 ounces) of flour. A normal loaf of bread weighing 1 ½ lbs. (a bread machine medium loaf) has 3,400 milligrams of sodium per loaf – several hundred milligams per slice or serving. Home bakers work with small amounts of salt and yeast. Bread machines use very small amounts for single loaves.
Measurement of salt and yeast by weight is desireable for home bakers and bread machine bakers. Few home bakers have scales precise enough.
Conversion? The great majority of recipes refer to standard ground table salt. For table salt: 1 tsp = 5.7 grams or .20 oz. Some fine crystal table salt on the market in the US weighs 7 grams per teaspoon. I do not pay attention to this information unless the recipe I am referring to has used a coarse or fine salt:
- America’s Test Kitchen/Cooks Illustrated The Science of Good Cooking (2012) lists several brands of kosher salt and sea salt and compares them to table salt, suggesting that Morton’s brand is the standard for table salt at 1 tsp = 7.15 g.
- Peter Reinhart, The Bread Baker’s Apprentice (Ten Speed Press, 2001) says on p. 28 that 1 tsp of table salt = .25 oz which converts to 7 grams.
The size of the salt crystals affects solubility, which can affect the distribution of salt in the dough, and effect of salt on yeast. However a gram of kosher salt works as well as a gram of table salt for baking bread.
Some sources say for instant yeast: 1 tsp = 3.15 grams. Peter Reinhart, The Bread Baker’s Apprentice (Ten Speed Press, 2001) says on p. 28 that 1 tsp instant yeast = .11 oz which converts to 3.12 grams. It is hard for home user to verify the weight of a teaspoon of instant yeast with home tools and methods. Instant yeast may vary slightly depending on the manufacturer, time and how the yeast has been stored and handled,