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 (C
24H
36O
18), caramelens (C
36H
50O
25), and caramelins (C
125H
188O
80). As the process occurs,
volatile chemicals such as
diacetyl 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, caramelization is a type of
non-enzymatic browning. Unlike the
Maillard reaction, caramelization is
pyrolytic, as opposed to being a reaction with
amino acids.
When caramelization involves the
disaccharide 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 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.
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
Inverted sugar syrup, also called invert syrup, invert sugar, simple syrup, sugar syrup, sugar water, bar syrup, syrup USP, or sucrose inversion, is a syrup mixture of the monosaccharides glucose and fructose, that is made by hydrolytic sa ...
to fructose and glucose
*
condensation reactions
* intramolecular bonding
*
isomerization of
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
ketoses
*
dehydration reactions
* fragmentation reactions
* unsaturated
polymer 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, 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
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 caramelization ...
, 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'', 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, a custard dish topped with sugar caramelized with a blowtorch
* Caramelized onions, which are used in dishes like
French onion soup. Onions require 30 to 45 minutes of cooking to caramelize.
* Caramelized potatoes
* Caramelized pears
*
Cola, of which some brands use caramelized sugar in small amounts for color
See also
*
List of cooking techniques
References
External links
Caramelizationat Science of Cooking
{{Cooking Techniques
Cooking techniques
Culinary terminology
de:Karamellisieren