Corn starch

Corn starch, also known as cornstarch or maize starch, is a fine white powder made from the seeds of corn plants. People have been using it for many years, and it was first made in Scotland. You can find it in many kitchens around the world because it is very useful.

One of the most common uses for corn starch is in cooking. It helps to thicken sauces and soups, making them smoother and more appealing. Besides this, corn starch is used to make corn syrup and other types of sugars.

Corn starch is not just for food. It is also used in many industries. It can be found in adhesives, paper products, and even in making textiles. Because it can help prevent things from sticking together, it is used as an anti-sticking agent in many products.

Corn starch can also be used in medical ways. For example, it helps provide glucose for people with a condition called glycogen storage disease.

When corn starch is mixed with certain liquids, it can change its behavior in interesting ways. With water, it becomes a material known as oobleck, which acts like a non-Newtonian fluid. This means it can feel hard when you hit it but flow like a liquid when you move slowly. With oil, corn starch can create something called an electrorheological fluid, which changes with electric fields. These special properties make corn starch fun to experiment with and study.

History

Corn starch was mostly used for making clothes stiff and for other factory jobs before 1851. In 1854, a man named John Polson from Scotland found a way to make pure starch from corn for cooking. His company, Brown & Polson, sold it as "Patented Corn Flour." They were experts at making starch for clothes and became the biggest starch makers in the UK.

Uses

Corn starch is mainly used in cooking and at home, but it has many other uses in different industries. It can be added to products as a chemical helper or used in medical treatments for certain illnesses.

Culinary

In cooking, corn starch is used to thicken liquids like soup, sauces, gravies, and custard. You mix it with a cooler liquid to make a paste. It is often chosen over flour because it makes things look clearer. When heated, the tiny parts of the starch come apart and mix together to make the liquid thicker. But if you keep boiling it, the liquid can get thinner again.

Corn starch is also added to powdered sugar to stop it from clumping. Sometimes, arrowroot starch is used instead of corn starch. Food makers add corn starch to foods like cheese and yogurt to save money. It is also put on chicken nuggets to help them get crispier when fried.

Non-culinary

Corn starch can be an ingredient in baby powder. It is used to make bioplastics, such as PLA for 3D printing, and in making airbags. It can also be used to make a kind of glue for paper and books, which dries with a nice shine. Mixing corn starch with salt can create a special craft material called salt ceramic.

Medical

Corn starch helps stop sticking on medical items made from natural latex, like condoms, diaphragms, and medical gloves. It can also help people with glycogen storage disease by giving them glucose to keep their blood sugar steady, and it can be used starting when children are about 6 to 12 months old.

Manufacture

Corn starch is made by a process called wet milling. First, the corn is soaked for 30 to 48 hours, which lets it ferment a little. Then, the part of the corn called the germ is separated from the endosperm. Both parts are ground while still wet. After that, the starch is washed away from other parts like the corn steep liquor, cereal germ, fibers, and corn gluten. Special machines called hydrocyclones and centrifuges help separate these parts. Finally, the starch is dried. Sometimes it is changed a bit to make it work better for certain jobs. The leftovers from each step are often used to make animal feed or corn oil.

Risks

Like many powders, corn starch can create dangerous situations when it becomes airborne and mixes with air. In 2015, an event in Taiwan happened when a corn starch-based powder got too hot, leading to a big explosion. Always follow safety warnings on products to avoid such risks.

Names and varieties

Corn starch is called corn starch in the United States and Canada. In the United Kingdom, Ireland, and some Commonwealth countries, it is known as cornflour. This is different from cornmeal in those places.

In Australia, cornflour is often made from wheat instead of corn. The starch comes from the wheat kernel and is sometimes called 'wheaten cornflour'.