Corn kernel

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Maize kernels Ab food 06.jpg
Maize kernels
Kernels on the cob VegCorn.jpg
Kernels on the cob

Corn kernels are the fruits of corn (called maize in many countries). Maize is a grain, and the kernels are used in cooking as a vegetable or a source of starch. The kernel comprise endosperm, germ, pericarp, and tip cap.

Contents

One ear of corn contains roughly 800 kernels in 16 rows. Corn kernels are readily available in bulk throughout maize-producing areas. They have a number of uses, including food and biofuel. Corn consists of the husk and the silk, often mistaken for the husk.

Description

Multicoloured kernels on a single corn cob CSIRO ScienceImage 3195 Maize or corn.jpg
Multicoloured kernels on a single corn cob

Corn kernels are the fruits of maize. Maize is a grain, and the kernels are used in cooking as a vegetable or a source of starch. The kernels can be of various colors: blackish, bluish-gray, purple, green, red, white and yellow. One ear of corn contains roughly 800 kernels in 16 rows. One hundred bushels of corn can contain upwards of 7,280,000 kernels.[ citation needed ] Transportation and packaging of dried clean corn kernels to non-producing areas adds to the cost.

Parts

The kernel of maize consists of a pericarp (fruit wall) fused to the seed coat. This type of fruit is typical of the grasses and is called a caryopsis. Maize kernels are frequently and incorrectly referred to as seeds. The kernels are about the size of peas, and adhere in regular rows round a white, pithy substance, which forms the ear.

Endosperm

About 82 percent of the corn kernel’s dry weight consists of endosperm. Starch is the primary source and it most widely used part of the kernel. It is known as the key component in fuel, sweeteners, bioplastics and other products.

Germ

The germ is the only living part of the corn kernel, also called its embryo. It consists of the important genetic information, vitamins, enzymes and minerals for the plant to grow. The germ accounts for 25 percent of the corn oils and it is a valuable part of the kernel.

Pericarp

The pericarp is the outer covering that protects the kernel and helps to maintain the kernel's nutrient value and moisture content. It is about 91% fiber. If the kernels are wet-milled, most of the pericarp will end up in the corn gluten feed.

Tip cap

The tip cap is the attachment point of the kernel to the corn cob, where the nutrient and water flow, and this is the only part that is not covered by the pericarp. It contains fiber.

Use

Corn kernels have a number of uses, including food, biofuel, and bioplastics.

Food

Bulk corn kernels Corn kernels.jpg
Bulk corn kernels

Corn is a popular food throughout the world in many forms. It is used in breakfast cereals in the Western world (as corn flakes) and it is a grain that can be eaten raw off the cob, although it is usually preferred cooked. It may be fed to animals or humans. In the United States, for economic reasons such as government subsidies, corn is the basis of many products, in the form of high fructose corn syrup, in favor of cane sugar.[ citation needed ] A genetic variant that accumulates more sugar and less starch in the ear is consumed as a vegetable and is called sweet corn.

When ground into flour, maize yields more flour, with much less bran, than wheat does. It lacks the protein gluten of wheat and, therefore, makes baked goods with poor rising capability.

It is also used in popcorn, a common snack in the US.

Biofuel

Corn kernels are used as pelletized fuel for pellet stoves and furnaces. Corn kernels are a natural pellet, which gives them an economic advantage over other man-made biomass pellets and wood pellets.

The use of corn and other grains as a renewable biofuel may have environmental and cost benefits, compared to other energy sources, and may create additional forms of revenue for farmers and other economic industries. However, the use of corn as a fuel stock may increase the price of corn and have adverse effects on corn as a food stock. In the United States, 5.6 million bushels of corn were used for ethanol production out of 14.6 million bushels produced, according to preliminary 2018 USDA data. [1] According to the U.S. Department of Energy's Alternative Fuels Data Center, "The increased ethanol [production] seems to have come from the increase in overall corn production and a small decrease in corn used for animal feed and other residual uses. The amount of corn used for other uses, including human consumption, has stayed fairly consistent from year to year." [2] This does not prove there was not an impact on food supplies: Since U.S. corn production doubled (approximately) between 1987 and 2018, it is probable that some cropland previously used to grow other food crops is now used to grow corn. It is also possible or probable that some marginal land has been converted or returned to agricultural use. That may have negative environmental impacts. Part of the production increase is also due to higher yields. [3] Achieving higher yields may entail greater use of irrigation, fertilizers, and controversial herbicides.

See also

Related Research Articles

<span class="mw-page-title-main">Sweet corn</span> Variety of corn

Sweet corn, also called sweetcorn, sugar corn and pole corn, is a variety of corn grown for human consumption with a high sugar content. Sweet corn is the result of a naturally occurring recessive mutation in the genes which control conversion of sugar to starch inside the endosperm of the corn kernel. Sweet corn is picked when still immature and prepared and eaten as a vegetable, rather than field corn, which is harvested when the kernels are dry and mature. Since the process of maturation involves converting sugar to starch, sweet corn stores poorly and must be eaten fresh, canned, or frozen, before the kernels become tough and starchy.

<span class="mw-page-title-main">Biofuel</span> Type of biological fuel produced from biomass from which energy is derived

Biofuel is a fuel that is produced over a short period from biomass, rather than by the very slow natural processes involved in the formation of fossil fuels, such as oil. Biofuel can be produced from plants or agricultural, domestic, or industrial biowaste. Biofuels are mostly used for transportation but can also be used for heating and electricity. Biofuels are regarded as a renewable energy source. However, the use of biofuel has been controversial because of the several disadvantages associated with the use of it. These include for example : the "food vs fuel" debate, biofuel production methods being sustainable or not, leading to deforestation and loss of biodiversity or not.

Field corn, also known as cow corn, is a North American term for maize grown for livestock fodder, ethanol, cereal, and processed food products. The principal field corn varieties are dent corn, flint corn, flour corn which includes blue corn, and waxy corn.

<span class="mw-page-title-main">Corn starch</span> Starch derived from corn (maize) grain

Corn starch, maize starch, or cornflour is the starch derived from corn (maize) grain. The starch is obtained from the endosperm of the kernel. Corn starch is a common food ingredient, often used to thicken sauces or soups, 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 manufacturing. It has medical uses as well, such as to supply glucose for people with glycogen storage disease.

Wheat flour is a powder made from the grinding of wheat used for human consumption. Wheat varieties are called "soft" or "weak" if gluten content is low, and are called "hard" or "strong" if they have high gluten content. Hard flour, or bread flour, is high in gluten, with 12% to 14% gluten content, and its dough has elastic toughness that holds its shape well once baked. Soft flour is comparatively low in gluten and thus results in a loaf with a finer, crumbly texture. Soft flour is usually divided into cake flour, which is the lowest in gluten, and pastry flour, which has slightly more gluten than cake flour.

<span class="mw-page-title-main">Ethanol fermentation</span> Biological process that produces ethanol and carbon dioxide as by-products

Ethanol fermentation, also called alcoholic fermentation, is a biological process which converts sugars such as glucose, fructose, and sucrose into cellular energy, producing ethanol and carbon dioxide as by-products. Because yeasts perform this conversion in the absence of oxygen, alcoholic fermentation is considered an anaerobic process. It also takes place in some species of fish where it provides energy when oxygen is scarce.

<span class="mw-page-title-main">Nixtamalization</span> Procedure for preparing corn to eat

Nixtamalization is a process for the preparation of maize, or other grain, in which the grain is soaked and cooked in an alkaline solution, usually limewater, washed, and then hulled. The term can also refer to the removal via an alkali process of the pericarp from other grains such as sorghum.

<span class="mw-page-title-main">Corn stover</span> Maize plant parts left in field after harvest

Corn stover consists of the leaves, stalks, and cobs of maize (corn) plants left in a field after harvest. Such stover makes up about half of the yield of a corn crop and is similar to straw from other cereal grasses; in Britain it is sometimes called corn straw. Corn stover is a very common agricultural product in areas of large amounts of corn production. As well as the non-grain part of harvested corn, the stover can also contain other weeds and grasses. Field corn and sweet corn, two different types of maize, have relatively similar corn stover.

<span class="mw-page-title-main">Waxy corn</span> Type of field corn

Waxy corn or glutinous corn is a type of field corn characterized by its sticky texture when cooked as a result of larger amounts of amylopectin. The corn was first described from a specimen from China in 1909. As this plant showed many peculiar traits, the American breeders long used it as a genetic marker to tag the existence of hidden genes in other maize breeding programs. In 1922 a researcher found that the endosperm of waxy maize contained only amylopectin and no amylose starch molecule in opposition to normal dent corn varieties that contain both. Until World War II, the main source of starch in the United States was tapioca, but when Japan severed the supply lines of the U.S., they forced processors to turn to waxy maize. Amylopectin or waxy starch is now used mainly in food products, but also in the textile, adhesive, corrugating and paper industry.

The United States produces mainly biodiesel and ethanol fuel, which uses corn as the main feedstock. The US is the world's largest producer of ethanol, having produced nearly 16 billion gallons in 2017 alone. The United States, together with Brazil accounted for 85 percent of all ethanol production, with total world production of 27.05 billion gallons. Biodiesel is commercially available in most oilseed-producing states. As of 2005, it was somewhat more expensive than fossil diesel, though it is still commonly produced in relatively small quantities.

Corn gluten meal is the principal protein of corn (maize) endosperm consisting mainly of zein and glutelin. It is a byproduct of corn processing that has historically been used as an animal feed. Despite the name, corn gluten does not contain true gluten, which is formed by the interaction of gliadin and glutenin proteins.

<span class="mw-page-title-main">Corn ethanol</span> Ethanol produced from corn biomass

Corn ethanol is ethanol produced from corn biomass and is the main source of ethanol fuel in the United States, mandated to be blended with gasoline in the Renewable Fuel Standard. Corn ethanol is produced by ethanol fermentation and distillation. It is debatable whether the production and use of corn ethanol results in lower greenhouse gas emissions than gasoline. Approximately 45% of U.S. corn croplands are used for ethanol production.

<span class="mw-page-title-main">Commercial sorghum</span>

Commercial sorghum is the cultivation and commercial exploitation of species of grasses within the genus Sorghum. These plants are used for grain, fibre and fodder. The plants are cultivated in warmer climates worldwide. Commercial Sorghum species are native to tropical and subtropical regions of Africa and Asia.

<span class="mw-page-title-main">Aventine Renewable Energy</span>

Aventine Renewable Energy Founded in 2003, was a bioethanol and biodiesel company based in Pekin, Illinois that produced and marketed these biofuels.

Biogasoline is a type of gasoline produced from biomass such as algae. Like traditionally produced gasoline, it is made up of hydrocarbons with 6 (hexane) to 12 (dodecane) carbon atoms per molecule and can be used in internal combustion engines. However, unlike traditional gasoline/petroleum based fuels, which are mainly composed from oil, biogasolines are made from plants such as beets and sugarcane or cellulosic biomass- substances normally referred to as plant waste.

<span class="mw-page-title-main">Food vs. fuel</span> Debate concerning diversion of food supply for biofuels production

Food versus fuel is the dilemma regarding the risk of diverting farmland or crops for biofuels production to the detriment of the food supply. The biofuel and food price debate involves wide-ranging views, and is a long-standing, controversial one in the literature. There is disagreement about the significance of the issue, what is causing it, and what can or should be done to remedy the situation. This complexity and uncertainty is due to the large number of impacts and feedback loops that can positively or negatively affect the price system. Moreover, the relative strengths of these positive and negative impacts vary in the short and long terms, and involve delayed effects. The academic side of the debate is also blurred by the use of different economic models and competing forms of statistical analysis.

<span class="mw-page-title-main">Maize</span> Genus of grass cultivated as a food crop

Maize, also known as corn in North American and Australian English, is a cereal grain first domesticated by indigenous peoples in southern Mexico about 10,000 years ago. The leafy stalk of the plant gives rise to inflorescences which produce pollen and separate ovuliferous inflorescences called ears that when fertilized yield kernels or seeds, which are botanical fruits. The term maize is preferred in formal, scientific, and international usage as the common name because it refers specifically to this one grain whereas corn refers to any principal cereal crop cultivated in a country. For example, in North America and Australia corn is often used for maize, but in England and Wales it can refer to wheat or barley, and in Scotland and Ireland to oats.

<span class="mw-page-title-main">Corn production in the United States</span> Production of maize crop in the United States

The production of corn plays a major role in the economy of the United States. The US is the largest corn producer in the world, with 96,000,000 acres (39,000,000 ha) of land reserved for corn production. Corn growth is dominated by west/north central Iowa and east central Illinois. Approximately 13% of its annual yield is exported.

<span class="mw-page-title-main">Corn wet-milling</span> Method of breaking down corn kernels

Corn wet-milling is a process of breaking corn kernels into their component parts: corn oil, protein, corn starch, and fiber. It uses water and a series of steps to separate the parts to be used for various products.

Dry milling of grain is mainly utilized to manufacture feedstock into consumer and industrial based products. This process is widely associated with the development of new bio-based associated by-products. The milling process separates the grain into four distinct physical components: the germ, flour, fine grits, and coarse grits. The separated materials are then reduced into food products utilized for human and animal consumption.

References

  1. "Alternative Fuels Data Center: Maps and Data - Corn Production and Portion Used for Fuel Ethanol". afdc.energy.gov. Retrieved 2019-08-29.
  2. "Alternative Fuels Data Center: Maps and Data - Corn Production and Portion Used for Fuel Ethanol". afdc.energy.gov. Retrieved 2019-08-29.
  3. "2009 Crop Year is One for the Record Books, USDA Reports". Nass.usda.gov. 12 January 2010. Archived from the original on 14 January 2010. Retrieved 4 April 2010.