Caramelization

Mirepoix (carrots, onions, and celery) being caramelized

Caramel of sucrose; all brown color is a result of browning, as sucrose is normally colorless

Caramelization (Template:Lang-en-GB) is the browning of sugar, a process used extensively in cooking for the resulting nutty flavor and brown color. As the process occurs, volatile chemicals are released, producing the characteristic caramel flavor.

Like the Maillard reaction, caramelization is a type of non-enzymatic browning. However, unlike the Maillard reaction, caramelization is pyrolysis, as opposed to reaction with amino acids.

When caramelization involves the disaccharide sucrose, it is broken down into the monosaccharides fructose and glucose.

Process

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

• equilibration of anomeric and ring forms
• sucrose inversion to fructose and glucose
• condensation reactions
• intramolecular bonding
• isomerization of aldoses to ketoses
• dehydration reactions
• fragmentation reactions
• unsaturated polymer formation.

Effects on caramelization

The process is temperature-dependent. Specific sugars each have their own point at which the reactions begin to proceed readily.

Caramelization temperatures

Sugar	Temperature
Fructose	110°C, 230°F
Galactose	160°C, 320°F
Glucose	160°C, 320°F
Sucrose	160°C, 320°F
Maltose	180°C, 356°F

The caramelization reactions are also sensitive to the chemical environment. By controlling the level of acidity (pH), the reaction rate (or the temperature at which the reaction occurs readily) can be altered. 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, caramelized, sweetened milk
• Dulce de leche, caramelized, sweetened milk
• Caramel candies
• Caramel corn, popcorn coated in caramel
• Caramelized onions, which are used in dishes like French onion soup. Onions require 30 to 45 minutes of cooking to caramelize.
• Caramelized potatoes
• Brown sugar
• Molasses
• Treacle

Note that the preparation of many "caramelized" foods also involves the Maillard reaction; particularly recipes involving protein and/or amino acid -rich ingredients.

See also

Media related to Caramelization at Wikimedia Commons

• Maillard reaction

External links

• Sugar in food management