INGREDIENTS IN BAKED GOODS
Flour, water, and leavening agents are the main ingredients that give bakery products their characteristic appearance, texture, and flavor. A leavening agent is a substance—such as air, steam, yeast, baking soda, or baking powder—that causes doughs and batters to expand by the release of gases within the mixtures, producing baked products with a porous structure. Eggs, milk, salt, shortening (a fat that is solid at room temperature), and sugar help modify these qualities. Various minor ingredients may also be used.
FLOUR
Flour is the ground seeds of cereal grains such as wheat, oats, barley, and rye. Several different flours or blends of flours can be used in baking. The type of flour used will affect the taste and texture of the baked goods.
The most popular flour in many countries is wheat flour. When mixed with the correct amount of water, its protein component forms an elastic network capable of holding gas and developing a firm spongy structure when baked. The substances contributing these properties are known as gluten. The suitability of a flour for a given purpose is determined by the type and amount of its gluten content. Low-protein, soft-wheat flour works well in cakes, pie crusts, cookies, and other products not requiring great expansion and elastic structure. High-protein, hard-wheat flour has a more elastic structure for greater expansion. It is used for bread, hard rolls, soda crackers, and Danish pastry.
LEAVENING AGENTS
Pie doughs and similar products are usually unleavened, meaning that they are flat and somewhat dense. However, most bakery products are leavened, or aerated, by gas bubbles developed naturally or folded in. Leavening may result from yeast or bacterial fermentation, from chemical reactions, or from the distribution in the batter of gases.
YEAST
Most commercial raised breads are leavened with baker’s yeast. Baker’s yeast is composed of living cells of a fungus (Saccharomyces cerevisiae). The yeast performs its leavening function in a process called fermentation. When water makes contact with starch in the flour, it releases sugars. (Starch is a carbohydrate—a substance made of the atoms carbon, hydrogen, and oxygen—that all green plants make.) The yeast consumes the sugars in the dough and produces carbon dioxide and grain alcohol. The carbon dioxide aerates the dough, making it “rise.” The grain alcohol helps develop the flavor and produce the freshly baked bread aroma.
BAKING SODA
Cakes, cookies, biscuits, and many other bakery products are leavened by adding baking soda (sodium bicarbonate) to form carbon dioxide bubbles. Baking soda reacts when it mixes with an acid such as buttermilk, yogurt, molasses, lemon juice, or cream of tartar (tartaric acid). Contact between the two substances promotes vigorous gas production while not changing the dough’s taste or texture.
BAKING POWDER
Instead of adding baking soda and leavening acids separately, most commercial bakeries and home bakers use baking powder. Baking powder is a mixture of baking soda and acids along with starch for stability in storage. Having all the ingredients in one product simplifies measuring. In addition, most commercial baking powders are “double-acting,” producing a little carbon dioxide during mixing and the rest during baking. This action eliminates excessive loss of leavening gas if the batter is not baked right away.
ENTRAPPED AIR
Angel food cakes, sponge cakes, and similar products are usually prepared without either yeast or chemical leavens. Instead, they are leavened by air entrapped in the product through vigorous beating. This method requires a foaming ingredient capable of retaining the air bubbles, such as egg whites. To produce a cake of fine and uniform internal structure, the pockets of air folded in during beating are rapidly subdivided into small bubbles with mixing utensils such as wire whips or whisks.
FATS AND OILS
Fats and oils are essential ingredients in nearly all bakery products. They add richness and tenderness to the finished products. They also help make the dough easier to handle during the preparation stages. The common fats used in bakery products are lard, beef fats, and hydrogenated vegetable oils. The most common processed vegetable oils are cottonseed and soybean, and corn, peanut, and coconut oils are used to a limited extent. Butter is used in some products to add flavor and texture. Home bakers commonly use butter, vegetable shortening, vegetable oils, or margarine. Fats occurring in other ingredients, such as egg yolks, chocolate, and nut butters, can act as a shortening if enough of the item is present.
LIQUIDS
Water is the liquid most commonly added to doughs. Water hydrates gluten, permitting it to form an elastic network that traps carbon dioxide gas and expands with it. Water affects every aspect of the finished product, and careful adjustment of the amount of liquid is necessary to make the dough or batter adaptable during processing. If dough is too wet, it will stick to equipment. If it is too dry, it will not shape or leaven properly. Milk is usually added to commercial preparations in dried form, and any moisture added from eggs and butter is usually minimal.
EGGS
Whole eggs help hold ingredients together during baking and provide structural support for finished baked goods. They also create tender, light textures and add moisture and flavor. Some baked goods use only the yolk or the egg white or use both parts but add them at different times. Egg yolks have a high percentage of fat. When used alone, they give bakery foods a rich flavor and velvety texture. Egg whites are important primarily for their texturizing function and, when beaten, give foams stability. Meringues and angel food cakes, for example, are dependent on egg white foams for their billowy structure.
Few commercial bakers use fresh eggs for ingredients because it is cheaper and more sanitary to use frozen or dried eggs. Many bakers use dried egg products because they are more convenient and store better than frozen eggs. Processed and stored correctly, dried egg products function the same as fresh eggs. However, if a lot of dry eggs are used, the flavor of the baked goods may suffer.
SWEETENERS
Small amounts of sugars are present in wheat flour. Sweeteners added to doughs include white and brown sugar, honey, corn syrup, and molasses. Sugars are important in the yeast-leavening process. Yeast feeds on the sugars and converts them to carbon dioxide. Sweeteners also add to a product’s flavor and texture. In addition, the color of the crust is related to the amount of sugars present. For example, a dough in which the sugars have been thoroughly depleted by yeast will produce a pale crust.
TYPES OF BAKED GOODS
YEAST-LEAVENED PRODUCTS
Most of the bakery foods consumed throughout the world are breads and rolls made from yeast-leavened doughs. The yeast-fermentation process produces a desirable flavor and texture. In addition, yeast cells add a wide assortment of vitamins and good quality protein.
BREADS AND ROLLS
Numerous types of breads exist, with some of the most popular being white, wheat, and rye. White bread is made from a simple mixture of refined flour (the ground inner layer, called the endosperm, of the wheat kernel), water, salt, and yeast. In the early to mid-20th century, many countries—including the United States, the United Kingdom, and Canada—required that white flour be enriched with various vitamins and minerals that were lost during the milling process.
Whole wheat bread is made using a meal made from the entire wheat kernel—the bran, endosperm, and germ. The bran and germ contain vitamins, minerals, protein, and fiber. Flour containing the entire wheat kernel typically produces a dense, rather tough, dark bread. Breads sold as wheat or part-whole-wheat products contain a mixture of whole grain meal and white flour.
Bread made from crushed or ground whole rye kernels, such as pumpernickel, is dark, tough, and coarse-textured. Rye flour with the bran removed can be mixed with wheat flour to produce a bread with better texture and color. In darker bread it is customary to add caramel color to the dough. Most rye bread is flavored with caraway seeds.
SWEET BREADS
Sweet goods made from mixtures similar to bread doughs include “raised” doughnuts, Danish pastries, and coffee cakes. Sweet doughs are richer in fat, milk, and sugar than bread doughs and often contain eggs. These ingredients alter the taste, produce flakier texture, and improve nutritional quality. Spices such as nutmeg, cinnamon, and ginger are frequently used for sweet-dough products. Other common ingredients include vanilla, nuts, peels or oils of lemon or orange, raisins, candied fruit pieces, jams, and jellies.
CHEMICALLY LEAVENED PRODUCTS
Many baked goods depend on the production of carbon dioxide from added chemical leavening agents such as baking soda or baking powder. Items produced by chemical leavening include cakes, cookies, muffins, American biscuits, corn bread, and some doughnuts.
HOT BREADS
Hot breads, such as American biscuits, muffins, and scones, constitute a large and important part of chemically leavened baked goods. (In the United Kingdom the term biscuit is used for a variety of small, crisp cakes, either sweetened—comparable to the American cookie—or unsweetened—comparable to the American cracker.) Hot breads consist of flour, baking powder, salt, and liquid, with varying amounts of eggs, sugar, and fat. Milk is often used for flavor and for its ability to add texture and crust color. Other variations include the addition of fruits, peppers, and cheese. In corn breads a considerable proportion of the flour is replaced by cornmeal.
Mixing and forming methods and the baking conditions affect the appearance, texture, and flavor of hot breads. For example, a batter suitable for making corn bread might also be used to make muffins. Each kind of finished product varies not only in appearance but also in flavor and texture.
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