Caramelization is a process of browning of

sugar Sugar is the generic name for sweet-tasting, soluble carbohydrates, many of which are used in food. Simple sugars, also called monosaccharides, include glucose, fructose, and galactose. Compound sugars, also called disaccharides or double ...

used extensively in cooking for the resulting sweet nutty flavor and brown color. The brown colors are produced by three groups of polymers: caramelans (C₂₄H₃₆O₁₈), caramelens (C₃₆H₅₀O₂₅), and caramelins (C₁₂₅H₁₈₈O₈₀). As the process occurs, volatile chemicals such as

diacetyl Diacetyl (IUPAC systematic name: butanedione or butane-2,3-dione) is an organic compound with the chemical formula (CH3CO)2. It is a yellow liquid with an intensely buttery flavor. It is a vicinal diketone (two C=O groups, side-by-side). Diacet ...

are released, producing the characteristic

caramel Caramel ( or ) is an orange-brown confectionery product made by heating a range of sugars. It can be used as a flavoring in puddings and desserts, as a filling in bonbons, or as a topping for ice cream and custard. The process of caramelizatio ...

flavor. Like the

Maillard reaction The Maillard reaction ( ; ) is a chemical reaction between amino acids and reducing sugars that gives browned food its distinctive flavor. Seared steaks, fried dumplings, cookies and other kinds of biscuits, breads, toasted marshmallows, and man ...

, caramelization is a type of

non-enzymatic browning Browning is the process of food turning brown due to the chemical reactions that take place within. The process of browning is one of the chemical reactions that take place in food chemistry and represents an interesting research topic regarding ...

. Unlike the

, caramelization is pyrolytic, as opposed to being a reaction with

amino acid Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although hundreds of amino acids exist in nature, by far the most important are the alpha-amino acids, which comprise proteins. Only 22 alpha am ...

s. When caramelization involves the

disaccharide A disaccharide (also called a double sugar or ''biose'') is the sugar formed when two monosaccharides are joined by glycosidic linkage. Like monosaccharides, disaccharides are simple sugars soluble in water. Three common examples are sucrose, lact ...

sucrose Sucrose, a disaccharide, is a sugar composed of glucose and fructose subunits. It is produced naturally in plants and is the main constituent of white sugar. It has the molecular formula . For human consumption, sucrose is extracted and refined ...

, it is broken down into the

monosaccharides Monosaccharides (from Greek ''monos'': single, '' sacchar'': sugar), also called simple sugars, are the simplest forms of sugar and the most basic units (monomers) from which all carbohydrates are built. They are usually colorless, water-solu ...

fructose Fructose, or fruit sugar, is a Ketose, ketonic monosaccharide, simple sugar found in many plants, where it is often bonded to glucose to form the disaccharide sucrose. It is one of the three dietary monosaccharides, along with glucose and galacto ...

and

glucose Glucose is a simple sugar with the molecular formula . Glucose is overall the most abundant monosaccharide, a subcategory of carbohydrates. Glucose is mainly made by plants and most algae during photosynthesis from water and carbon dioxide, using ...

Process

Caramelization is a complex, poorly understood process that produces hundreds of chemical products, and includes the following types of reactions: * equilibration of

anomeric In carbohydrate chemistry, a pair of anomers () is a pair of near-identical stereoisomers that differ at only the anomeric carbon, the carbon that bears the aldehyde or ketone functional group in the sugar's open-chain form. However, in order for ...

and ring forms * sucrose inversion to fructose and glucose *

condensation reaction In organic chemistry, a condensation reaction is a type of chemical reaction in which two molecules are combined to form a single molecule, usually with the loss of a small molecule such as water. If water is lost, the reaction is also known as a ...

s * intramolecular bonding *

isomerization In chemistry, isomerization or isomerisation is the process in which a molecule, polyatomic ion or molecular fragment is transformed into an isomer with a different chemical structure. Enolization is an example of isomerization, as is tautomeriz ...

aldose An aldose is a monosaccharide (a simple sugar) with a carbon backbone chain with a carbonyl group on the endmost carbon atom, making it an aldehyde, and hydroxyl groups connected to all the other carbon atoms. Aldoses can be distinguished from keto ...

s to

ketose A ketose is a monosaccharide containing one ketone group per molecule. The simplest ketose is dihydroxyacetone, which has only three carbon atoms. It is the only ketose with no optical activity. All monosaccharide ketoses are reducing sugars, be ...

s *

dehydration reaction In chemistry, a dehydration reaction is a chemical reaction that involves the loss of water from the reacting molecule or ion. Dehydration reactions are common processes, the reverse of a hydration reaction. Dehydration reactions in organic che ...

s * fragmentation reactions * unsaturated

polymer A polymer (; Greek '' poly-'', "many" + ''-mer'', "part") is a substance or material consisting of very large molecules called macromolecules, composed of many repeating subunits. Due to their broad spectrum of properties, both synthetic a ...

formation

Effects of caramelization

The process is temperature-dependent. Specific sugars each have their own point at which the reactions begin to proceed readily. Impurities in the sugar, such as the

molasses Molasses () is a viscous substance resulting from refining sugarcane or sugar beets into sugar. Molasses varies in the amount of sugar, method of extraction and age of the plant. Sugarcane molasses is primarily used to sweeten and flavour foods ...

remaining in

brown sugar Brown sugar is unrefined or partially refined soft sugar. Brown Sugar may also refer to: Arts, entertainment, and media Films * ''Brown Sugar'' (1922 film), a 1922 British silent film directed by Fred Paul * ''Brown Sugar'' (1931 film), a 1931 ...

, greatly speed the reactions. Caramelization reactions are also sensitive to the chemical environment, and the reaction rate, or temperature at which reactions occur most readily, can be altered by controlling the level of acidity ( pH). The rate of caramelization is generally lowest at near-neutral acidity (pH around 7), and accelerated under both acidic (especially pH below 3) and basic (especially pH above 9) conditions.

Uses in food

Caramelization is used to produce several foods, including: * Caramel sauce, a sauce made with caramel * ''

Confiture de lait ''Dulce de leche'' (; pt, doce de leite), also known as caramelized milk, milk candy or milk jam in English, is a confection from Latin America prepared by slowly heating sugar and milk over a period of several hours. The resulting substance, w ...

'' and ''

Dulce de leche ''Dulce de leche'' (; pt, doce de leite), also known as caramelized milk, milk candy or milk jam in English, is a confection from Latin America prepared by slowly heating sugar and milk over a period of several hours. The resulting substance, wh ...

'', caramelized, sweetened milk *

Caramel Caramel ( or ) is an orange-brown confectionery product made by heating a range of sugars. It can be used as a flavoring in puddings and desserts, as a filling in bonbons, or as a topping for ice cream and custard. The process of caramelizatio ...

candies * Creme Caramel, and the similar

crème brûlée ''Crème brûlée'' or ''crème brulée'' (; ), also known as burnt cream or Trinity cream, and virtually identical to the original crema catalana, is a dessert consisting of a rich custard base topped with a layer of hardened caramelized sugar ...

, a custard dish topped with sugar caramelized with a blowtorch * Caramelized onions, which are used in dishes like

French onion soup French onion soup (French: ''soupe à l’oignon'' ) is a soup usually based on meat stock and onions, and often served gratinéed with croutons or a larger piece of bread covered with cheese floating on top. Ancient in origin, the dish under ...

. Onions require 30 to 45 minutes of cooking to caramelize. * Caramelized potatoes * Caramelized pears *

Cola Cola is a carbonated soft drink flavored with vanilla, cinnamon, citrus oils and other flavorings. Cola became popular worldwide after the American pharmacist John Stith Pemberton invented Coca-Cola, a trademarked brand, in 1886, which was imita ...

, of which some brands use caramelized sugar in small amounts for color

References

External links

Caramelization
at Science of Cooking {{Cooking Techniques Cooking techniques Culinary terminology de:Karamellisieren

Process

Effects of caramelization

Uses in food

See also

References

External links