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A leavening agent (sometimes called just leavening or leaven) is a substance used in doughs and batters that causes a foaming action intended to lighten and soften the finished product. Dough is a paste made out of any Cereals (grains or leguminous crops by mixing the Flour with a small amount of Water. Batter is a liquid mixture usually based on one or more Flours combined with liquids such as Water, Milk or Beer. The leavening agent reacts with moisture, heat, acidity, or other triggers to produce gas (usually carbon dioxide and sometimes ethanol) that becomes trapped as bubbles within the dough. Carbon dioxide ( Chemical formula:) is a Chemical compound composed of two Oxygen Atoms covalently bonded to a single When a dough or batter is mixed, the starch in the flour mixes with the water in the dough to form a matrix (often supported further by proteins like gluten or other polysaccharides like pentosans or xanthan gum), then gelatinizes and "sets"; the holes left by the gas bubbles remain, giving breads, cakes, and other baked goods their soft, sponge-like textures. Starch, CAS # 9005-25-8 Chemical formula (C6H10O5n is a Polysaccharide Gluten is a composite of the proteins Gliadin and Glutenin. These exist conjoined with Starch, in the Endosperms of some Xanthan gum is a Polysaccharide used as a Food additive and Rheology modifier. Bread is a Staple food prepared by Baking a Dough of Flour and Water. Cake is a form of Food that is usually sweet and often baked.

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Biological leaveners

Main article: Yeast

Microorganisms that release carbon dioxide as part of their life cycle can be used to leaven products. Yeasts are a growth form of eukaryotic Microorganisms classified in the kingdom Fungi, with about 1500 Species currently described Carbon dioxide ( Chemical formula:) is a Chemical compound composed of two Oxygen Atoms covalently bonded to a single Varieties of yeast are most often used, particularly Saccharomyces species (i. Yeasts are a growth form of eukaryotic Microorganisms classified in the kingdom Fungi, with about 1500 Species currently described Saccharomyces is a Genus in the kingdom of fungi that includes many species of Yeast. e. baker's yeast), though some recipes also rely on certain bacteria. Baker's yeast is the common name for the strains of Yeast commonly used as a Leavening agent in Baking Bread and related products where it converts Yeast leaves behind waste byproducts (particularly ethanol and some autolysis products) that contribute to the distinctive flavor of yeast breads. In biology autolysis may refer to the destruction of a cell through the action of its own Enzymes It may also refer to the digestion of an enzyme by another molecule In sourdough breads, the flavor is further enhanced by various lactic or acetic acid bacteria. Sourdough (or more formally natural leaven or Levain) refers to the process of leavening Bread by capturing wild Yeasts The Bacteria ( singular: bacterium) are a large group of unicellular Microorganisms Typically a few Micrometres in length bacteria have

Leavening with yeast is a process based on fermentation, physically changing the chemistry of the dough or batter as the yeast works. Unlike chemical leavening, which usually activates as soon as the water combines the acid and base chemicals, yeast leavening requires proofing, which allows the yeast time to reproduce and consume carbohydrates in the flour. Proofing (also called proving) is a step in creating Yeast Breads and baked goods where the yeast is allowed to Leaven the dough

Yeast can also be used to make alcoholic beverages like beer. Beer is the world's oldest and most widely consumed Alcoholic beverage and the third most popular drink overall after water and tea The resulting cast-off yeast, known as barm, can be used as a leavener and was probably ancestral to the use of modern pure-cultured yeast. Barm is the foam or scum formed on the top of liquor (ie fermented alcoholic beverages such as Beer or Wine, or feedstock for Hard liquor

While not as widely used, bacterial fermentation is sometimes used, occasionally providing a drastically changed flavor profile from a yeast fermentation; salt rising bread, which uses a culture of the Clostridium perfringens bacterium, is a well-known example. Salt rising (or salt risen bread is bread in which the bacterium Clostridium perfringens is used to leaven the bread rather than Yeast or Baking soda. Clostridium perfringens (formerly known as Clostridium welchii) is a Gram-positive, rod-shaped anaerobic, spore-forming Bacterium

Some typical biological leaveners are:

Chemical leaveners

Chemical leaveners are chemical mixtures or compounds that typically release carbon dioxide or other gases when they react with moisture and heat; they are almost always based on a combination of acid (usually a low molecular weight organic acid) and an alkali (though ammonia-based leaveners are also available, though in decreasing quantity). Carbon dioxide ( Chemical formula:) is a Chemical compound composed of two Oxygen Atoms covalently bonded to a single Ammonia is a compound with the formula N[[hydrogen H3]] It is normally encountered as a Gas with a characteristic pungent Odor They usually leave behind a chemical salt. Salt is a Dietary mineral composed primarily of Sodium chloride that is essential for Animal life but toxic to most land plants Chemical leaveners are used in quick breads and cakes, as well as cookies and numerous other applications where a long biological fermentation is impractical or undesirable. A quick bread is a type of Bread which is Leavened with chemical leaveners such as Baking powder, Sodium bicarbonate, or Cream of tartar Cake is a form of Food that is usually sweet and often baked. In the United States and Canada, a cookie is a small flat-baked treat usually round containing milk flour eggs and sugar etc

Since the chemical expertise required to create a functional chemical leaven without leaving behind off-flavors from the chemical precursors involved, such substances are often mixed into premeasured combinations for maximum results. These are generally referred to as baking powders. Baking powder is a dry chemical Leavening agent used in cooking mainly baking

Chemical leavening agents include:

Mechanical leavening

Creaming is the process of beating sugar crystals and solid fat (typically butter) together in a mixer. Carbonate of potash redirects here For one of potassium carbonate's impure forms see Potash. Creaming is used to refer to several different Culinary processes Butter is a Dairy product made by churning fresh or fermented Cream or Milk. A mixer is a Kitchen Appliance intended for mixing Folding, beating and whipping food ingredients This integrates tiny air bubbles into the mixture, since the sugar crystals physically cut through the structure of the fat. Creamed mixtures are usually further leavened by a chemical leavener. This is often used in cookies. In the United States and Canada, a cookie is a small flat-baked treat usually round containing milk flour eggs and sugar etc

Using a whisk on certain liquids, notably cream or egg whites, can also create foams through mechanical action. A whisk is a Cooking utensil used in food preparation to blend Ingredients smooth or to incorporate air into a mixture in a process known as For the 1993 hip-hop single by the Wu-Tang Clan see CREAM CREAM is an acronym for Cognitive Reliability Error Analysis Method a Albumen redirects here For other uses see Albumen (disambiguation. This is the method employed in the making of sponge cakes, where an egg protein matrix produced by vigorous whipping provides almost all the structure of the finished product. Sponge cake is a cake based on Flour (usually Wheat flour Sugar, and eggs sometimes leavened with Baking powder, that derives its

The Chorleywood Bread Process uses a mix of biological and mechanical leavening to produce bread; while it is considered by food processors to be an effective way to deal with the soft wheat flours characteristic of British Isles agriculture, it is controversial due to a perceived lack of quality in the final product. The Chorleywood Bread Process, or CBP was developed in 1961 by the Flour Milling and Baking Research Association at Chorleywood and is now used to make 80% of the UK’s The process has nevertheless been adapted by industrial bakers in other parts of the world.

Other leaveners

Steam and air are used as leavening agents when they expand upon heating. Uses A Steam engine uses the expansion of steam in order to drive a Piston or Turbine to perform Mechanical work. Temperature and layers The temperature of the Earth's atmosphere varies with altitude the mathematical relationship between temperature and altitude varies among five To take advantage of this style of leavening, the baking must be done at high enough temperatures to flash the water to steam, with a batter that is capable of holding the steam in until set. This effect is typically used in popovers and Yorkshire puddings, and to a lesser extent in Tempura. A popover is a light hollow roll made from an egg batter similar to that used in making Yorkshire pudding. Yorkshire pudding is a dish that originated in Yorkshire but attained wider popularity is a classic Japanese dish of deep fried battered Vegetables or Seafood.

Nitrous oxide is used as a propellant in aerosol whip cream cans. Nitrous oxide, commonly known as " laughing gas," is a Chemical compound with the Chemical formula N 2 O. When the gas boils out of the cream, it also instantly creates a foam.

References

See also


Chametz (חָמֵץ (also Chometz or Chumetz) refers to bread grains and leavened products that are not consumed on the Jewish holiday of Passover

Dictionary

leavening agent

-noun

  1. Any organism or substance used to make baked goods rise.
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