Maize, also known as maize, is a cereal grain that was first domesticated around 10,000 years ago by indigenous people in southern Mexico. The plant’s leafy stalk produces pollen inflorescences and separate ovular inflorescences called ears that contain fruit kernels or seeds. In several parts of the world, maize has become a staple food, with total maize production surpassing that of wheat or rice. Maize is widely cultivated throughout the world, and maize is produced annually at a higher weight than any other crop.
In the world, maize is the most abundantly produced cereal. It is cultivated on all continents, except Antarctica. There are about 50 species and they consist of various colors, textures, and shapes and sizes of grains. The most popular cultivated varieties of maize include white, yellow, and red. Depending on the area, the white and yellow varieties are preferred by most people.
Historical (Origin) of Maize
Most scholars agree that maize was domesticated in Mexico’s Tehuacán Valley. Latest analysis at the beginning of the 21st century has somewhat altered this view; researchers now refer to the nearby Balsas River Valley in south-central Mexico as the origin of domestication. Later, maize spread across the Americas from this region along two major pathways. This is consistent with a model based on an archeological record suggesting that maize was diversified in the highlands of Mexico before it spread to the lowlands.
Maize was spread to Lower Central America by 7600 BP [5600 BC] and transferred to the inter-Andean valleys of Colombia between 7000 and 6000 BP [5000–4000 BC].
According to a genetic analysis by Embrapa, corn production from Mexico in South America was adopted in two main waves: the first, more than 6000 years ago, spread through the Andes. Proof of agriculture has been found in Peru since around 6700 years ago. The second wave, some 2000 years ago, through the lowlands of South America. It was thought that starting about 2500 BC, the crop spread through most of the Americas.
Since the arrival of Europeans in 1492, Spanish settlers ate maize, and explorers and merchants took it back to Europe and brought it to other nations. Spanish settlers preferred wheat bread to maize, cassava or potatoes. Maize flour could not be substituted for wheat for communion bread because, in Christian tradition, only wheat could undergo transubstantiation and be converted into the body of Christ. Some Spaniards were afraid that consuming indigenous food, which they did not deem nutritious, would weaken and risk becoming Indians. “In the view of Europeans, it was the food they ate, even more than the environment in which they lived, that gave Amerindians and Spaniards both their distinctive physical characteristics and their characteristic personalities.” Given these issues, the Spaniards ate maize. Archeological data from Florida sites suggests that it has also been cultivated.
Maize has expanded to the rest of the world because of its potential to thrive in different climates. It was grown in Spain just a few decades after the voyage of Columbus, and then spread to Italy, West Africa and elsewhere.
Types (Varieties) of Maize
There are a number of different types of maize, the most common varieties are as listed below:
- Dent (Zea mays indenata): Dent corn is often used as feed for animals, in agricultural goods or in the manufacturing of processed food. Dent corn is often widely referred to as “field” corn. The dent kernals, either white or yellow, produce both hard and soft starch that is indented at maturity.
- Flint (Zea mays indurata): Flint corn, also known as Indian corn, is used for similar uses as dent corn. Flint corn is characterized by a rough outer shell and kernals with a variety of colors from white to red.
- Sweet (Zea saccharata or Zea rugosa): Sweet corn is primarily eaten on the cob, or it can be canned or frozen for future consumption. Sweet corn is seldom used for feed or flour. Sweet corn is extra sweet because it contains more natural sugars than other types of corn. (Field corn contains 4% sugar at the same stage standard sweet corn contains 10% sugar.) Almost 50% of the sugar can be converted to starch only 24 hours after sweet corn is picked, so it is best to eat it fresh!
- Flour (Zea mays amylacea): Flour corn is used in baked goods because it has a soft, starch-filled grain that is easy to grind. Flour corn is predominantly white, but it can be cultivated in other colours, such as blue corn.
- Popcorn (Zea mays everta): Popcorn, a type of flint corn, has a soft starchy core surrounded by a very hard outer shell. When popcorn is heated, the normal moisture within the kernal transforms to steam, which causes enough pressure for the kernal to explode. When the kernal explodes, the white starchy mass that you want to eat forms. All kinds of corn will pop to a degree, but they won’t actually have enough starch to transform inside out, or an exterior layer that causes enough pressure to pop.
Uses of Maize
Maize can also be used in a number of other ways:
Human Food
Maize and cornmeal (ground dried maize) are a staple food in many parts of the world. Maize is used to make cornstarch, an important ingredient in home cooking, and many industrial food products. Maize starch can be hydrolyzed and enzymatically treated for the production of syrups, especially high fructose corn syrup, a sweetener; and also fermented and distilled for the production of grain alcohol. Corn flour is used to produce cornbread and other baked goods.
Maize can also be harvested and eaten in an unripe state while the kernels are fully grown but still tender. Usually, unripe maize must be cooked to make it palatable; this can be achieved by merely boiling or roasting the entire ears and consuming the kernels straight off the cob.
Maize has suboptimal levels of the essential amino acids tryptophan and lysine, which account for its lower status as a protein source. Proteins of beans and legumes, however, supplement those of maize.
Feed and Fodder for Livestock
Maize is a significant producer of both crop feed and feed for livestock. It is fed to the cattle in a number of ways. When used as a grain harvest, the dried kernels are used as feed. They are also stored in a cob for storage in a grain crib, or they may be shelled off for storage in a grain container. The farm that consumes the feed can produce it, buy it on the market, or some of it. When the grain is used for feed, the rest of the plant (corn stover) will later be used as feed, bedding (litter) or soil modification. When the whole maize plant (grain plus stalks and leaves) is used for feed, it is typically cut all at once and ensiled as digestibility and palatability are better in the ensiled state than in the dry form. Maize silage is one of the most valuable forage items for ruminants. Before the start of widespread ensiliation, it was customary to collect corn in shocks after harvesting, where it was further dried. With or without a corresponding transfer to the shelter of the stable, it was then kept for weeks or months before it was fed to the livestock. Today, ensiling can occur not only in siloes, but also in silage wrappers. However, in the tropics, maize can be harvested all year round and fed to the animals as a green forage.
Chemicals
Corn starch can also be produced in plastics, garments, adhesives and many other chemical products. Corn steep liquor, an abundant watery by-product of the maize wet milling process, is commonly used in the biochemical industry and research as a culture medium for many forms of microorganisms. Chrysanthemin is present in purple corn and is used as a food coloring agent.
Bio-fuel
‘Feed maize’ is increasingly used for heating purposes; specialized maize stoves (similar to wood stoves) are available and either feed maize or wood pellets are used to produce heat. Maize cobs are also used as a fuel source for biomass. Maize is relatively inexpensive and home-heating furnaces have been built that use maize kernels as fuel. They feature a large hopper that feeds equally sized maize kernels (or wood pellets or cherry pits) into the fire.
Maize is increasingly used as a feed source for the processing of ethanol fuel. Ethanol is combined with gasoline to reduce the amount of contaminants produced as used to drive motor vehicles.
Nutritional Value and Chemical Composition of Maize
100 grams of boiled yellow corn contains the following:
- Calories: 96
- Water: 73%
- Protein: 3.4 grams
- Carbohydrates: 21 grams
- Sugar: 4.5 grams
- Fiber: 2.4 grams
- Fat: 1.5 grams
Carbohydrates
Corn, like all cereal grains, is mostly comprised of carbohydrates. Starch is the primary carbohydrate, accounting for 28–80 per cent of its dry weight. Corn also supplies limited quantities of sugar (1–3 per cent). Sweet corn, or sugar corn, is a special low starch variety with a higher sugar content of 18% of the dry weight. Most sugar is sucrose. Despite sugar in sweet corn, it is not a high-glycemic product with a low to medium glycemic level (GI). The GI is an indicator of how easily carbohydrates are digested. Foods that are high in this index can cause an unhealthful spike in blood sugar.
Fiber
Corn has a decent amount of fiber in it. Although the fiber content of various varieties of corn varies, it is usually around 9–15 per cent of the dry weight. The primary fibers in corn are insoluble, such as hemicellulose, cellulose and lignin.
Protein
Corn is a healthy source of protein. Depending on the variety, the protein content varies from 10% to 15%. The most abundant proteins in corn are known as zeins, accounting for 44–79% of the total protein content. Overall, the protein content of zeins is poor due to the absence of certain essential amino acids. Zeins have many commercial uses as they are used in the manufacture of adhesives, inks and coatings for pills, sweets and nuts.
Health Benefits of Maize
Maize has many health advantages due to the availability of quality nutrients it provides. Besides being a tasty complement to every meal, its abundance in phytochemicals protects against certain chronic diseases. Some of the health benefits of maize as seen below:
Protects against Constipation
The fiber content in one cup of corn is 18.4% of the recommended daily amount. It tends to alleviate stomach issues, such as constipation and hemorrhoids, since maize is a whole grain. Dietary fiber can help to loosen and soften stools, facilitate daily removal and prevent straining. This mechanism is carried out by inducing the peristaltic movement and the production of gastric juice and bile. Through applying bulk to loose stools, the chances of irritable bowel syndrome (IBS) and diarrhea can be significantly decreased.
Facilitates Weight Gain
Corn, particularly the yellow variety, is a rich source of calories and a staple in many countries. The calorific value of sweet yellow and white corn is 96 calories per 100 grams. That’s why it’s always turned into a fast weight gain.
Source of Essential Minerals
Corn provides a variety of important minerals that can help ensure good growth and disease prevention. It is an essential source of iron, zinc, copper, manganese, magnesium and phosphorus. However, the nutritional content can differ based on how it is harvested and processed. The nutritious value is better retained when consumed whole or as popcorn. Steaming, boiling or roasting decreases the nutritious content. It also contains trace minerals such as selenium, which are difficult to obtain in most diets. Phosphorus is important for the regulation of normal development, bone health and optimal kidney function. Magnesium is required to sustain normal heart rhythm and increase bone mineral density.
Protects the Heart
Corn oil has been found to have an anti-atherogenic effect on cholesterol levels, decreasing the risk of multiple cardiovascular diseases. Corn oil, in particular, is the safest way to boost heart wellbeing and is derived from the fact that corn is similar to the ideal mix of fatty acids. This helps omega-3 fatty acids to eliminate unhealthy LDL or poor cholesterol and replace it at binding sites. This will decrease the risks of arteries being clogged, lower blood pressure and lower the likelihood of heart disease and stroke.
Consumption of corn husk oil reduces LDL plasma or low cholesterol levels by decreasing cholesterol absorption in the body. This reduction in LDL cholesterol does not mean a reduction in HDL or healthy cholesterol, which can have positive effects on the body. These include the elimination of coronary disease, avoidance of atherosclerosis, and general scavenging of free radicals in the body.
Eye and Skin Care
Yellow corn is a rich source of beta-carotene that forms vitamin A in the body and is important for the preservation of healthy vision and skin. It can also help the protection of the skin and mucous membranes, as well as the immune system. The sum of beta-carotene in the body that is not converted to vitamin A serves as a very good antioxidant, like all carotenoids, which can resist disease.
Manages Diabetes
Consumption of maize helps to regulate non-insulin-dependent diabetes mellitus (NIDDM) and is effective against hypertension due to the presence of phenolic phytochemicals in whole corn. Phytochemicals can monitor the absorption and release of insulin in the body, which can reduce the risk of spikes and declines in people with diabetes and help them sustain a healthier lifestyle. Yellow corn is a rich source of beta-carotene that forms vitamin A in the body and is important for the preservation of healthy vision and skin.
Cosmetic Benefits
Cornstarch is used in the manufacture of many cosmetic products and can also be used topically to soothe skin rashes and inflammation. Its products can be used to supplement carcinogenic petroleum products, which are the key ingredients of many cosmetic products.