In cooking, reduction is the process of

thickening A thickening agent or thickener is a substance which can increase the viscosity of a liquid without substantially changing its other properties. Edible thickeners are commonly used to thicken sauces, soups, and puddings without altering thei ...

and intensifying the flavor of a liquid mixture such as a

soup Soup is a primarily liquid food, generally served warm or hot (but may be cool or cold), that is made by combining ingredients of meat or vegetables with stock, milk, or water. Hot soups are additionally characterized by boiling solid ing ...

sauce In cooking, a sauce is a liquid, cream, or semi-solid food, served on or used in preparing other foods. Most sauces are not normally consumed by themselves; they add flavor, moisture, and visual appeal to a dish. ''Sauce'' is a French word t ...

wine Wine is an alcoholic drink typically made from fermented grapes. Yeast consumes the sugar in the grapes and converts it to ethanol and carbon dioxide, releasing heat in the process. Different varieties of grapes and strains of yeasts are m ...

, or

juice Juice is a drink made from the extraction or Cold-pressed juice, pressing of the natural liquid contained in fruit and vegetables. It can also refer to liquids that are flavored with concentrate or other biological food sources, such as meat ...

simmering Simmering is a food preparation technique by which foods are cooked in hot liquids kept just below the boiling point of water (lower than ) and above poaching temperature (higher than ). To create a steady simmer, a liquid is brought to a boil, ...

boiling Boiling is the rapid vaporization of a liquid, which occurs when a liquid is heated to its boiling point, the temperature at which the vapour pressure of the liquid is equal to the pressure exerted on the liquid by the surrounding atmosphere. Th ...

. Reduction is performed by simmering or boiling a liquid such as a

stock In finance, stock (also capital stock) consists of all the shares by which ownership of a corporation or company is divided.Longman Business English Dictionary: "stock - ''especially AmE'' one of the shares into which ownership of a company ...

, fruit or vegetable juices, wine, vinegar, or a sauce until the desired concentration is reached by evaporation. This is done without a lid, enabling the vapor to escape from the mixture. Different components of the liquid will evaporate at slightly different temperatures, and the goal of reduction is to drive away those with lowest points of evaporation. While reduction does concentrate the flavors left in the pan, reducing too much will drive away all liquid in the sauce, leaving a "sticky, burnt coating" on the pan. Sauces from basic

brown sauce Brown sauce is a condiment commonly served with food in the United Kingdom and Ireland, normally dark brown in colour. The taste is either tart or sweet with a peppery taste similar to that of Worcestershire sauce. Brown sauce is typically eate ...

Béchamel sauce Bechamel sauce ( ) is a sauce traditionally made from a white roux (butter and flour in a 1:1 mixture by weight) and milk. Bechamel may also be referred to as besciamella (Italy), besamel (Greece), or white sauce (U.S.). French, Italian and Greek ...

and even

tomato sauce Tomato sauce (also known as ''salsa roja'' in Spanish or ''salsa di pomodoro'' in Italian) can refer to many different sauces made primarily from tomatoes, usually to be served as part of a dish, rather than as a condiment. Tomato sauces are c ...

are simmered for long periods (from 1 to 10 hours) but not boiled. Simmering not only develops the maximum possible flavor, but also allows impurities to collect at the top and be skimmed off periodically as the sauce cooks. Boiling diffuses the impurities into the liquid and results in a bitter taste and unclear stock. Broths are also simmered rather than boiled, and for the same reasons.

Examples

Common preparations involving reductions include: *

Consommé In cooking, a consommé is a type of clear soup made from richly flavoured stock or broth that has been clarified, a process that uses egg whites to remove fat and sediment. Consommé has three English pronunciations: traditionally in the UK, t ...

s, reduced and clarified

stocks Stocks are feet restraining devices that were used as a form of corporal punishment and public humiliation. The use of stocks is seen as early as Ancient Greece, where they are described as being in use in Solon's law code. The law describing ...

* Gravies *

Gastrique Gastrique is caramelized sugar, deglazed with vinegar or other sour liquids, used as a sweet and sour flavoring for sauces. The gastrique is generally added to a fond, reduced stock or brown sauce. It is also used to flavor sauces such as toma ...

s, sauces involving both acidic and sweet components *

Pan sauce Deglazing is a cooking technique for removing and dissolving browned food residue from a pan to flavor sauces, soups, and gravies. When a piece of meat is roasted, pan- fried, or prepared in a pan with another form of dry heat, a deposit ...

s *

Syrup In cooking, a syrup (less commonly sirup; from ar, شراب; , beverage, wine and la, sirupus) is a condiment that is a thick, viscous liquid consisting primarily of a solution of sugar in water, containing a large amount of dissolved sugars ...

References

Cooking techniques Culinary terminology {{cooking-stub