Corn starch, maize starch, or cornflour (

British English British English (BrE, en-GB, or BE) is, according to Lexico, Oxford Dictionaries, "English language, English as used in Great Britain, as distinct from that used elsewhere". More narrowly, it can refer specifically to the English language in ...

) is the

starch Starch or amylum is a polymeric carbohydrate consisting of numerous glucose units joined by glycosidic bonds. This polysaccharide is produced by most green plants for energy storage. Worldwide, it is the most common carbohydrate in human diets ...

derived from corn (

maize Maize ( ; ''Zea mays'' subsp. ''mays'', from es, maíz after tnq, mahiz), also known as corn ( North American and Australian English), is a cereal grain first domesticated by indigenous peoples in southern Mexico about 10,000 years ago. ...

) grain. The starch is obtained from the endosperm of the

kernel Kernel may refer to: Computing * Kernel (operating system), the central component of most operating systems * Kernel (image processing), a matrix used for image convolution * Compute kernel, in GPGPU programming * Kernel method, in machine lea ...

. Corn starch is a common food ingredient, often used to thicken sauces or

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 soli ...

s, and to make corn syrup and other sugars. Corn starch is versatile, easily modified, and finds many uses in industry such as adhesives, in paper products, as an anti-sticking agent, and

textile Textile is an umbrella term that includes various fiber-based materials, including fibers, yarns, filaments, threads, different fabric types, etc. At first, the word "textiles" only referred to woven fabrics. However, weaving is not t ...

manufacturing. It has medical uses as well, such as to supply glucose for people with glycogen storage disease. Like many products in dust form, it can be hazardous in large quantities due to its

flammability A combustible material is something that can burn (i.e., ''combust'') in air. A combustible material is flammable if it ignites easily at ambient temperatures. In other words, a combustible material ignites with some effort and a flammable mat ...

—see dust explosion. When mixed with a fluid, corn starch can rearrange itself into a non-Newtonian fluid. For example, adding water transforms corn starch into a material commonly known as oobleck while adding oil transforms corn starch into an electrorheological (ER) fluid. The concept can be explained through the mixture termed "cornflour slime".

History

Until 1851, corn starch was used primarily for starching laundry and for other industrial uses. A method to produce pure culinary starch from maize was patented by John Polson of Brown & Polson, in Paisley,

Scotland Scotland (, ) is a country that is part of the United Kingdom. Covering the northern third of the island of Great Britain, mainland Scotland has a border with England to the southeast and is otherwise surrounded by the Atlantic Ocean to th ...

in 1854. This was sold as "Patented Corn Flour". Brown & Polson were muslin manufacturers who had been producing laundry starch for the Paisley shawl industry and would become the largest starch producers in the UK.

Uses

Although mostly used for cooking and as a household item, corn starch is used for many purposes in several industries, ranging from its use as a chemical additive for certain products, to medical therapy for certain illnesses.

Culinary

United States Food Admininstration corn products poster

Corn starch is used as a thickening agent in liquid-based foods (e.g.,

, sauces, gravies,

custard Custard is a variety of culinary preparations based on sweetened milk, cheese, or cream cooked with egg or egg yolk to thicken it, and sometimes also flour, corn starch, or gelatin. Depending on the recipe, custard may vary in consistency f ...

), usually by mixing it with a lower-temperature liquid to form a paste or slurry. It is sometimes preferred over

flour Flour is a powder made by grinding raw grains, roots, beans, nuts, or seeds. Flours are used to make many different foods. Cereal flour, particularly wheat flour, is the main ingredient of bread, which is a staple food for many c ...

alone because it forms a translucent, rather than opaque mixture. As the starch is heated over , the molecular chains unravel, allowing them to collide with other starch chains to form a mesh, thickening the liquid ( Starch gelatinization). However, continued boiling breaks up the molecules and thins the liquid. Cornstarch is usually included as an anticaking agent in powdered sugar (icing or confectioner's sugar). A common substitute is arrowroot starch, which replaces the same amount of corn starch. Food producers reduce production costs by adding varying amounts of corn starch to foods, for example to cheese and yogurt. Chicken nuggets with a thin outer layer of corn starch allows increased oil absorption and crispness after the latter stages of frying.

Non-culinary

Baby powder Baby powder is an astringent powder used for preventing diaper rash and for cosmetic uses. It may be composed of talc (in which case it is also called talcum powder) or corn starch. It may also contain additional ingredients like fragran ...

may include corn starch among its ingredients. Corn starch can be used to manufacture bioplastics and may be used in the manufacture of airbags. Adhesive can be made from corn starch, traditionally one of the adhesives that may be used to make paste papers. It dries with a slight sheen compared to wheat starch. It may also be used as an adhesive in book and paper conservation.

Medical

Corn starch is the preferred anti-stick agent on medical products made from natural

latex Latex is an emulsion (stable dispersion) of polymer microparticles in water. Latexes are found in nature, but synthetic latexes are common as well. In nature, latex is found as a milky fluid found in 10% of all flowering plants (angiosper ...

, including

condom A condom is a sheath-shaped barrier device used during sexual intercourse to reduce the probability of pregnancy or a sexually transmitted infection (STI). There are both male and female condoms. With proper use—and use at every act of inte ...

s, diaphragms, and medical gloves. Corn starch has properties enabling supply of glucose to maintain blood sugar levels for people with glycogen storage disease. Corn starch can be used starting at age 6–12 months allowing glucose fluctuations to be deterred.

Manufacture

The corn is

steeped Steeping is the soaking of an organic solid, such as leaves, in a liquid (usually water) to extract flavours or to soften it. The specific process of teas being prepared for drinking by leaving the leaves in heated water to release the flavour a ...

for 30 to 48 hours, which ferments it slightly. The germ is separated from the endosperm and those two components are ground separately (still soaked). Next the starch is removed from each by washing. The starch is separated from the corn steep liquor, the cereal germ, the fibers and the corn gluten mostly in hydrocyclones and centrifuges, and then dried. (The residue from every stage is used in animal feed and to make corn oil or other applications.) This process is called wet milling. Finally, the starch may be

modified Modified may refer to: * ''Modified'' (album), the second full-length album by Save Ferris * Modified racing, or "Modifieds", an American automobile racing genre See also * Modification (disambiguation) * Modifier (disambiguation) Modifier may ...

for specific purposes.

Risks

Like many other powders, corn starch is susceptible to dust explosions. It is believed that overheating of a corn starch-based powder on 27 June 2015, initiated the Formosa Fun Coast explosion in Taiwan, despite warnings on the packaging indicating that the material is flammable.

Names and varieties

* Called ''corn starch'' in the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., federal district, five ma ...

and

Canada Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tota ...

. The term ''corn flour'' refers to cornmeal that is very finely milled; or, to masa flour. * It is called ''cornflour'' in the

United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the European mainland, continental mainland. It comprises England, Scotlan ...

Ireland Ireland ( ; ga, Éire ; Ulster Scots dialect, Ulster-Scots: ) is an island in the Atlantic Ocean, North Atlantic Ocean, in Northwestern Europe, north-western Europe. It is separated from Great Britain to its east by the North Channel (Grea ...

Israel Israel (; he, יִשְׂרָאֵל, ; ar, إِسْرَائِيل, ), officially the State of Israel ( he, מְדִינַת יִשְׂרָאֵל, label=none, translit=Medīnat Yīsrāʾēl; ), is a country in Western Asia. It is situated ...

and some

Commonwealth A commonwealth is a traditional English term for a political community founded for the common good. Historically, it has been synonymous with " republic". The noun "commonwealth", meaning "public welfare, general good or advantage", dates from th ...

countries. Distinct in these countries from cornmeal.

References

External links

American Corn Refiners Association
{{corn Maize products Starch Edible thickening agents 1840 introductions