The peanut, or groundnut (Arachis hypogaea) is native to South America, Mexico and Central America. It is an annual herbaceous plant growing to 50 cm. The flowers are yellow with reddish veining.

After pollination, the fruit develops into a legume 3 to 7 cm long containing 1 to 4 seeds, which forces its way underground to mature. As the seeds within the legume mature, they develop a brown cover coating.

Although a nut in the culinary sense, in the botanical sense the fruit of the peanut is a woody, indehiscent legume and not a nut. Peanuts are also known as earthnuts, goobers, goober peas, pindas, jack nuts, pinders, manila nuts, monkey nuts and monkey balls.

Evidence demonstrates that peanuts were domesticated in prehistoric times in Peru. Archeologists estimate the oldest specimens to date back to 7,600 years. The Spanish traders found the “earth cacao” being offered for sale in the marketplace of Mexico City, as they are still offered by street vendors there today.

The plant was later spread worldwide by European traders. Cultivation in the English colonies of North America was popularized by African Americans. In South America, the peanut is thought to have first grown in Argentina or Bolivia, where the wildest strains grow today.

The peanut gained Western popularity when it came to the United States from Africa. It had become popular in Africa after being brought there from Brazil by the Portuguese around 1800.

The pods begin in the orange veined, yellow, pea-like flowers, which are borne in auxiliary clusters above ground. Following pollination, the flowers fade. The stalks at the bases of the ovaries, called pegs, elongate rapidly, and turn downward to bury the fruits several inches in the ground to complete their development.

The pods act in nutrient absorption. The fruits have wrinkled shells that are constricted between the two to four seeds. The mature seeds resemble other legume seeds, such as beans, but they have paper-thin seed coats, as opposed to the usual, hard legume seed coats.

Peanuts grow best in light, sandy loam soil. They require five months of warm weather, and an annual rainfall of 500 to 1000 mm or the equivalent in irrigation.

Cultivation in China
The peanut was introduced in China by the Portuguese traders in the 1600s and another variety by American missionaries in the 1800s. During the 1980s peanut production began to increase greatly so that as of 2006 China was the world’s largest peanut producer.

Nutritional value
Peanut contains 21 percent carbohydrates, 7 percent saturated fat, 24 percent mono-unsaturated fat, 16 percent poly-unsaturated fat, 25 percent proteins and a number of vitamins and minerals in notable proportions.

Since 1990 the gold standard for measuring protein quality, peanut protein and other legume proteins such as soy protein is the nutritional equivalent of meat and eggs for human growth and health.

Peanut oil is a mainly mono-saturated fat, much of which is oleic acid, the healthful type of fat that has been implicated for skin health. Some say peanuts are an unbalanced source of fat because they have only trace amounts of required Omega-3 fats.

Peanuts are also one of the highest sources of vitamin B3, also called niacin and thus contributes to brain health, brain circulation and blood flow. Vitamin B3 has been shown to enhance memory thus making peanuts a memory boosting food.

Also due to the peanuts high niacin content, peanuts could be useful in reversing hallucinatory experience, delusional thinking or wide mood and energy shifts of some psychological disturbances. Some studies even show promising results in treatment of schizophrenia with niacin.

Peanuts and Antioxidants
New research shows peanuts rival the antioxidant content of many fruits. Roasted peanuts rival the antioxidant content of blackberries and strawberries, and are far richer in antioxidants than apples, carrots or beets.

Research conducted by a team of University of Florida scientists, published in the journal Food Chemistry, shows that peanuts contain high concentrations of antioxidant polyphenols, and that roasting can increase peanuts’ overall antioxidant content by as much as 22 per cent.

A University of Florida research team reveals that peanuts are rich in antioxidants which protect cells from damage linked to heart disease and cancer. They also contain high levels of protein and “good” monounsaturated fat.

But, fat content makes them unsuitable for losing weight. According to the US researchers, peanuts are high in levels of polyphenols, a family of chemicals commonly found in foods, which have strong antioxidant properties. The nuts contain a high level of one particular polyphenol called p-coumaric acid.

The researchers discovered that roasting peanuts can increase the level of the acid in nuts, thereby increasing their overall antioxidant content by up to 22 per cent.

They warn against the tendency to eat salted peanuts, as it is not good for one to have high levels of salt. It is also observed that compared to foods long-considered rich in antioxidants, mostly fruits and berries, peanuts come out somewhere in the middle.

The best way to eat peanuts is to combine them with mixed fruits so that they are not covered in salt and one gets the health benefits of the fruit.

Groundnut is grown in nearly 100 countries with China, India, Sub-Saharan African countries and Central and South America in the forefront. Developing countries account for 96% of the global area of groundnut cultivation and 92 per cent of the global production.

Asia accounts for 58 per cent of the global groundnut area and 67 per cent of the groundnut production with an annual growth rate of 1.28 per cent for area, 2.00 per cent for production.

Groundnut is a valuable cash crop for millions of small-scale farmers in the semi-arid tropics. It generates employment on the farm and in marketing, transportation and processing. In 2004 groundnut was grown on 24 million hectares worldwide with a total production of 36 million metric tons.

Groundnut is the 13th most important food crop of the world. It is the world’s 4th most important source of edible oil and 3rd most important source of vegetable protein. Groundnut seeds contain high quality edible oil (50 pc), easily digestible protein (25 pc) and carbohydrates (20 pc).

Groundnut is a valuable source of E, K, and B vitamins. It is the richest plant source of thiamine (B1), and is also rich in niacin, which is low in cereals.

Article Courtesy » Executive Knowledge Lines

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