Corn
(Zea mays -- Family Gramineae)
The term "corn" is used mainly in North America for the sweeter types of the grain, while the word "maize" is used elsewhere in the world. Like other grains, corn is a member of the grass family, but is distinguished from its relations by its relatively short growing season and its large seed head. Two giant New World grasses, teosinte and Tripsacum, plus a recent discovery, Zea diploperennis, are believed to be closely involved in the formation of the modern varieties.
The oldest known remains of its the wild ancestor are grains of pollen found in an archaeologist's drill core taken from excavations for the foundations of a new building in Mexico City. These grains were estimated to be about 70,000 years old and date from a time before human habitation. Another archeological site in Tehuacán, also in Mexico, revealed small cobs of less than an inch in length. The wild maize gathered at this site, estimated to be from about 5500 BCE, indicates that the grain had been deliberately sown, and not just gathered from wild plants. Another site in New Mexico produced a similar grain. That site was estimated to be from about 4500 BCE. This primitive maize had about fifty grains to an ear and looked very much like small popcorn.
The oldest South American ruins are found in Peru and date from 1000 BCE. At that time, the whole continent appeared to be well-inhabited with people moving from one area to another. Therefore, the development of the corn plant came about as a matter of human selection rather than a botanical accident. It appeared that varieties were bred by Maya and Inca farmers almost to the size of modern ones. Early American civilizations were based on maize; and the life of the Aztec revolved around the milpa or cornfield. Multicoloured types ranged from blue, to scarlet, brown to almost black seeds and predominated in South America. However, it did not become a staple crop in North America until after 800 CE. The first types introduced to Europe in the 16th century were from Central America, and valued for both their "cobs" and the yellow meal. Corn also flourished in Spain, France, Italy, the Balkans, and Portugal. Since then, sweet corn and maize have become the third most important cereal crop in the world after wheat and rice. Maize is often grown in the company of beans, which supply nitrogenous compounds to replenish the soil robbed by growing corn alone.
Corn is a single species that exists in a bewildering number of forms. By the time the Europeans arrived in the Americas, there were some 300 major maize varieties grown from Canada to Chile. Now there are thousands, and many of them are hybrids; but all can be classified within six main types: pod, dent, flint, pop, flour, and sweetcorn. Each has a distinctive appearance and use, which is determined by the structure of the grains. There are three basic colour groups: yellow, white, and bi-colour. Exotic colours include purple, red, blue, and calico. Cobs can range from two feet in length down to the two-inch miniatures. As a matter of interest, the average ear of corn has about 800 kernels in sixteen rows. There is always an even number of rows (eight to thirty-two), having as many as 1,200 grains on each cob. Obviously, those must be the two-footers that occur in some species and not the average ear of corn.
A few peculiarities are found in the maize plant. One is that the modern varieties have only one or two ears per plant, which are covered by protective leaves that form a husk. This prevents the ripened kernels from falling to the ground for self-propagation, thereby necessitating cultivation. Another is that the stem bears both male and female flowers. but at some distance from each other. The male flowers form the "silk tassel" at the top of the stem, while the female flowers form some distance below. Each strand of silk extends from one undeveloped grain; and, when this strand of silk catches pollen blown off neighbouring male flowers by the wind, the female flower can become a mature ear of corn.
Nearly half of the world's maize is grown in North America today. However, more than 90% is fed to animals. Russia, China, and South America grow much of the rest of the world's supply; but, since the majority is consumed locally, only about 10% enters the world trade. Although corn is the only grain eaten as a vegetable, Europe never really adopted the love for it that Americans did and fed most of it to their animals. This is quite the opposite of what happened with such other grains as barley and oats, where Europeans made them a staple food for humans, but Americans fed them to their animals.
There are more than 500 different by-products obtained from corn, with the flour and starch playing a major role in manufactured foodstuffs, as well as in the making of adhesives, pharmaceuticals, cosmetics, cloth, and paper. Glucose syrups made with corn are found in the majority of sweetened processed foods and drinks. A vast array of synthetic rubber can now be made in part from processed maize. Laundry starch, as well as the food starch, is made from corn. Cigarette papers are made from the inner husks, and explosives and packaging material are made from the pith. But the most popular form is in the very adulterated breakfast cereal. To make "corn flakes", the kernels of corn have their fiber and nutrient-rich outer layers removed, leaving the starchy kernel to be cooked, rolled, and toasted, followed by the addition of an assortment of synthetic vitamins, flavourings, salt, and sugar, rendering it nothing like the original grain.
In the Americas, the Indian Squanto has historically been credited as being the mentor of the newly-arrived colonists, and, in 1620, was formally given recognition for this help and guidance. In fact, until about 1920, there was a variety of corn named in his honour, Squantum, which has since disappeared. Since there was no way for these early settlers to obtain fresh milk or dairy products (cows had not yet arrived from the Old World), mothers would mix crushed fresh corn with the juice of boiled hickory nuts and chestnuts to use as a baby food.
In Mitchell, South Dakota, the Corn Palace is a mighty tourist attraction with its annual redecoration of the exterior that uses over 2,000 bushels of corn. Nothing on the walls have been dyed or coloured in any way, reminding us of the many varieties of corn that do exist, and in so many colours. The red corn used is a variety called Bloody Nothing, the speckled corn is Calico or Indian Corn, and the nearly black kernels are usually Blue Flint. Almost a million tourists flock to Mitchell on an annual basis. It can be quite an educational trip for young and old alike.
Corn is a high-carbohydrate, high-starch food. The carbohydrates in corn consist of sugar, starch, and food fiber, amounting to about 81% of the total content. The most plentiful sugar in sweet corn is glucose. Other nutrients include fat, calcium, potassium, iron, provitamin A, B complex vitamins, and Vitamin C; but not all of these nutrients are readily available to the human body. All varieties of sweet corn are good sources of Vitamin C and niacin. However, about 80% of the niacin is unavailable to the human body because it is bound into insoluble carbohydrate/protein/nitrogen compounds. Corn also has some non-heme iron, which is found in plant food and which the body does not absorb very well. Vegetarians have learned to circumvent this problem by eating foods rich in Vitamin C at the same time, helping the iron become better absorbed.
Corn is also a moderately good source of plant proteins but zein, its major protein, is deficient in the essential amino acids lysine, cystine, and tryptophan. By combining corn with a legume rich in these deficient amino acids, a complete protein dish has been created. For example, the traditional Latin American combination of corn tortillas and beans makes the meal complete in protein.
Central and South American peoples developed a number of delicious ways to eat maize, including a sweet porridge, the traditional tortilla, and, of course, tamales. In Mexico, tamales are a national dish traditionally made with meats dripping in fats and rolled in a corn paste, wrapped in corn husks, and then steamed. Our Mexican daughter-in-law, Martha, makes wonderfully delicious tamales without meats or fats, but instead, using beans, peppers, and other vegetables. This popular recipe is available only in her cookbook, however, which is given out during their Spanish-immersion programs.
The major types of maize are as follows:
Sweet corn: It is the corn-on-the-cob variety, good also for canning and freezing. There are about 100 different subspecies, including Sweet Sue, Gold Cup, Silver Queen, Platinum Lady, Butter-and-Sugar. They are easily recognized by their wrinkled exterior. Their sweetness is the result of a "genetic defect" bred into them which prevents the sugars in the kernel from being completely transformed into starch.
Field or dent corn: It is the type that is usually dried right in the field, creating a "dent" at the top of the kernel. It is basically the commercial variety in which about 90% is used for animal feed and the rest goes into making breakfast cereals, cornstarch, corn oils and syrups. Any one of the several hundred processed food products on the market that list "corn" as an ingredient will more than likely be from the field or dent corns. The grains are large and starchy and were the foundation in the creation of the "corn belt" of the US. This corn was always used more as animal fodder than for human consumption.
Indian or flint corn: It produces the hard kernels that give it the "flint" name. They are the popular multicoloured ears often used for decorative purposes. Colours range from blue, to red, yellow, orange, purple, and black kernels. When ground, this type of corn is quite edible and was a favourite of the American Indians, who did not mind the hard skins as they usually dried the grain before using it later anyway.
Squaw, soft, or blue corn: It has larger, and sometimes huge, ears with big, starchy grains that were mainly blue in colour. This type was often made into flour and one of the principal types grown by the Hopi Indians and nearby tribes, including the Zuñi and Navajo. These tribes grew blue corn for hundreds of years. The dark indigo gave a unique colour, texture, and intense corn flavour to their tribal breads. It was possibly the earliest form of sweet corn cultivated by the settlers; but, since it is rather difficult to harvest and has a long growing season, it is likely that the younger generations did not want to put that much effort into its cultivation and began to use other varieties. By 1984, this variety was in danger of becoming extinct with only 500 acres devoted to the crop in the entire US. However, the blue corn is making a remarkable comeback, and a host of blue corn products are now available on the market in the form of cornmeal, pancake mix, tortillas, and cornbread.
Popcorn: It is one of the all-time favourites. It is a very specific and individual type of corn and has been grown for at least 5,000 years. The Incas were known to have used strings of popcorn in their ceremonies, having continued down to modern day traditional usage. The early settlers popped it as, no doubt, the first instant breakfast cereal. Commercial history of popcorn in the US began in Chicago in the late 19th century when Charles C. Cretors developed a machine for large-quantity popping. Popcorn's popularity soared even more when the now-famous Orville Redenbacher started developing modern varieties around 1941, leading to types that can now be popped to forty times their original kernal size. What makes popcorn unique is that it contains a very hard hull and about 14% internal moisture. With nowhere to go when the kernel is heated, the moisture develops into steam; and the rest is delicious history. Popcorn is so popular that a special institute was organized offering facts relating to this variety. Popcorn is one of the healthiest snacks -- if it is not popped in oil or butter or salt added. Eaten plain, it has only about 30-40 calories per cup. The theatre versions often topples the 200-calorie mark for the same amount.
Forms of corn include the following:
Dried whole corn: It can be found in any colour -- white, yellow, or blue -- and used for home grinding into meal or flour or in the preparation of hominy.
Cornmeal: It is also found in colours and is ground to a medium-fine consistency, with the corn germ intact. Some kinds are labelled "stone ground" while others say "water ground". This only refers to the power source and not to either stone or metal milling. A good stone-ground cornmeal does not require the addition of other flours to prevent crumbling. However, since blue cornmeal is denser than the white or yellow, equal portions of flour are usually required in a recipe.
Corn germ: It is the central core of the kernel and is the part where the new plant sprouts or germinates. Ten pounds of corn is required to provide one pound of germ and is used in exactly the same way as wheat germ. It has a popcorn flavour and is highly perishable, so it needs to be kept cold.
Corn bran: It is the layer of the kernel that is used in exactly the same way as wheat, oat, or rice bran.
Whole hominy: It comes in yellow or white and is known by various names: moté, posole, samp, and nixtamal. Small kernels of whole, dried amber-coloured corn are processed in the same way as whole hominy, and called "chicos". Whole hominy is also available in cans. The process involves the taking of the whole corn and treating it with slaked (hydrated) lime or a combination of unslaked lime, calcium carbonate, lye, or wood ash. The lime, combined with water, acts to loosen the hulls and partially "cook" the kernels, as well as puffing them up. The corn is then washed to remove the hulls and the lime and then dried. At the stage before the corn is dried, it is put through a grinder and then molded into tortillas and baked. After drying, it can be ground into what is called "masa harina". It is the only cornmeal or flour that can be used to make tortillas.
Hominy grits: It was originally developed by the native Americans, who called it "corn without skin". As far back as 1607, settlers who came ashore at Jamestown were offered bowls of "rockahominy". It is made from un-degerminated, coarsely ground (preferably stone ground) white or yellow corn and comes in fine, medium, and coarse grinds, as well as in an instant version.
Corn flour: It comes in white, yellow, or blue and ground to a finer consistency than cornmeal. It can be used in combination with any other flour to make any number of dishes requiring flour.
Cornstarch: In England, it is called "corn flour"; so travellers, note the difference. Cornstarch is derived from a high-starch variety of corn called indentata (Dent varieties). A finely-milled silken powder is taken from the endosperm layer of the grain and used as a thickening agent. Not only used as a food, cornstarch has a long history of being used in folk medicine. For example, a paste is made and applied to the skin to ward off prickly heat caused by the sun or used in conjuction with baby powders.
Puffed corn: It is a process which produces round, light, and airy puffs of corn that can be used in the same manner as puffed wheat or rice.
Corn oil, syrups, and pastas: These and a whole range of other forms are available on the market today.
Cornsilk: It can be gathered or purchased and used to make a tea that soothes the urinary passages and acts as a diuretic. It can be beneficial in cases of kidney stones and cystitis, but, to be effective, several cups of the infusion should be taken each day.
Baby corn: It is also known as miniature corn and mini-corn cobs. In Thai cookbooks, they are referred to as candle corn. These miniature ears come from any variety and are not a special type. They are picked just as the silk first appears, when they reach a length of two to four inches and one-half inch in diameter. There are two systems for harvesting baby corn. Both are very labour-intensive. The first has a dual purpose. The top ears are retained for either grain production or marketable sweet corn, and the lower ears are picked by hand before pollination. Since most varieties produce one to three ears per stalk, and since these must be hand-gathered, the economics of such a crop are poor. The second system is based on almost twice the density of planting, with all ear shoots being harvested at once as baby corn. These bite-sized delicacies have long been a popular fresh vegetable in Asia, but now, gourmets from all over the world are demanding their presence.
Corn mushroom, corn smut, corn soot, huitlacoche, cuitlacoche (Ustilago maydis) These are names for a black mushroom-like fungus eaten as a delicacy in Mexico where it is sautéed in oil and garlic and used as a stuffing in tortillas and tamales. Americans call it "smut", while the original Aztec word is even less appealing. "Cuitlacochin" translates simply into a 'bad ear of corn', but is based on the word "cuitlatl", which means dirt, tumor, abscess, and excretment. Wisely, some chefs have made the name more appealing and dubbed it the Mexican truffle. How this "food" evolved from the disdain of the Aztecs into an American delicacy is nothing short of typical. Whether the fungus enters the corn spontaneously or is introduced by inoculation, it develops darkly inside the kernels, causing them to swell into grotesque shapes and sizes. The inky result is dense and pasty, but mild and sweet when cooked, in fact, having a gentler flavour than some paler mushrooms. The fungus-gorged ears of corn vary from gray to red to blue to black and are sold during the rainy season in Mexican markets. They are also quickly sold out in Paris markets and are a very popular item on some New York menus. Some chefs reportedly struggle to find enough, despite using 100 pounds of it every week. High labour costs makes it an unprofitable crop for many farmers as the ears must be hand picked at the right point in time so that the bulging kernels will not burst open. Then they must be transported in such a way to keep them in good shape.
