Peanut

Peanut ( Arachis hypogaea )

The peanut ( Arachis hypogaea ), also known as Ashanti, arachis or Cameroon walnut, is a species in the subfamily of the Fabaceae ( Faboideae ) within the legume family ( Fabaceae or Leguminosae). This crop comes from the New World, and is therefore in some Swiss cantons also Spanish Lamb called. The fruit is botanically not a true nut peanut, but a legume and thus related, for example, with the pea and bean species. The English common name of the peanut, peanut ( in German " pea nut" ), refers to the botanical belonging to the legume.

The similarity to botanical nuts is due to the nature of the seed, the consistency, the high fat content and the relatively low proportion of starch. Compared to real nuts, the proportion of omega -3 fatty acids is low. In contrast to most other legumes, peanuts are raw but edible. The allergenic potential as compared to other food allergens relatively high.

• 5.1 Nutrition Facts
• 5.2 Health hazards

• 8.1 Notes and references

Description

Appearance and leaf

The peanut is an annual herbaceous plant. The yellowish hairy to bald stalk is independently upright to creeping and 6-80 cm, but usually 30 cm long.

The alternate arranged leaves are divided into petiole and leaf blade. The 3.7 to 10 cm long petiole is covered with long twisted trichomes. The paired pinnate leaf blade usually has two pairs on the rachis against constantly confronting with 1 to 10 mm only short -stalked leaflets. Those with a length of 1.1 to 5.9 cm and a width of 0.5 to 3.4 cm ovate - oblong to ovate leaflets are wrong - paper- with largely rounded base and the end is blunt or emarginate with spike tip. The occupied with long hair leaf areas have about ten lateral nerves on each side of the central nerve. The edge of the leaflets is ciliated. The 2-4 cm, membranous, hairy stipules are partially adherent to the petiole.

Inflorescence and flower

The flowering period extends from May to August. The pendent inflorescences are reduced to a bloom. Of the membranous bracts is the lowest with a length of 1 to 1.4 cm and a width of 4 to 5 mm ovate - lanceolate with two peaks, the others are similar in size but in two columns.

The sessile, hermaphrodite flowers are zygomorphic and fünfzählig double perianth. Of the five membranous, narrow sepals are four fused to a 4-6 mm thin tube and the fifth is free; they increase in size to form seeds. The 0.7 to 1.3 cm long crown has the typical structure of the Fabaceae. The five petals are yellow to golden yellow, often with red nerves. The spread flag is almost circular and at the base only briefly nailed with ausgerandeter tip. The two free slender wings are oblong to obliquely ovate and auriculate. The beaked, long ovoid and bent- inward boat is shorter than the wings. Of the original ten stamens are missing one or two. All stamens are fused with each other. There are two forms in the anthers, long and short alternate. The single first almost seated elongated carpel usually having two to four, often up to six ovules. The " Gynophor " or " Karpophor " said base of carpel extended to a length of 1 to 20 cm and curves after fertilization - as the fruit passes under the earth. The fast transient thin stylus is relatively long, but shorter than the calyx. The small scar is sparsely hairy.

Fruit and seeds

The legumes are geokarp, that are located in the ground, hence the name " Peanut ". Those with a length of 2 to 6 cm and a diameter of 1 to 1.5 cm oblong, incurved legumes contain one to four, rarely up to six seeds and are constricted between them something. These underground legumes do not open automatically. The thick fruit walls have a net-like surface. The one with a length of 1 to 2 cm and a diameter of 0.5 to 1 cm has almost egg-shaped, light -brown seed two abundant oil-bearing seed leaves ( cotyledons ). The fruits ripen from July to September. The seed coat in the mature seed is brown, papery and tastes bitter, so it is usually removed prior to further processing or consumption of the cores.

Set of chromosomes

The chromosome number of tetraploid species is 2n = 40

Origin and cultivation

Originally native to the Andes of South America, the cultivation of groundnut has spread as oil crop all over the tropics and subtropics since their growing importance.

Archaeologists dated the oldest known finds of domesticated peanuts from Peru to an age of 7600 years. From there, the peanut cultivation spread to other parts of South and Mesoamerica where the Spanish conquistadors in the markets of Tenochtitlan on the tlalcacáhuatl ( Nahuatl for " peanut ", literally " cocoa bean of the earth"; derived from this word, the Spanish and French terms for the peanut, cacahuete or cacahuète ) were attentive.

In Brazil, was the peanut as early as 2000 years ago in the cultivation and was brought to Africa from there during the slave trade. Today, the peanut is grown in warm areas worldwide. The main growing areas are West Africa, China, India, North and South America.

The harvested crops are first dried down in the water content of 40 to 5 to 10 percent. In warm countries this is done outdoors in temperate climates with artificial heat. After drying, the nuts are threshed or broken and optionally unmolded.

Trade

The main producing countries and also the main exporters of peanuts are the United States, Argentina, Sudan, Senegal and Brazil. The exports of these five countries together account for 71 percent of total world exports of peanuts, with the U.S. in recent years took a leading role in the export.

Although India and China also produce substantial amounts of peanuts, their share of international trade with less than 4 percent is negligible. The peanuts are usually used to meet domestic demand. So 90 percent of domestically produced peanuts are in India, for example, used to make peanut oil, and only a very small amount is released for export.

The main customers for peanuts are the countries of the European Union, Canada and Japan, which together are responsible for 78 percent of global peanut imports. In the European Union, Cyprus is a peanut- producing country. The import into the EU is mainly used for foods such as roasted peanuts or as part of candy.

Peanut products

Peanuts are often roasted and salted in the trade, as well as ingredients in sweets. The traded with shell peanuts are also roasted in the rule; at unroasted peanuts would avoid the risk of mold poisoning.

The processing of peanut products are used in many ways in the food industry and also serve as a renewable raw material in the chemical industry, in cosmetics and in significant amounts as oil-containing feed additive in agricultural animal production.

An important peanut product is especially popular in India and China as a cooking oil peanut oil. It is also used as an herbal remedy. Other products include peanut butter and peanut flips.

Ingredients and health aspects

Nutrition Facts

Peanuts dry roasted, without salt per 100 g

• Calorific value 2448 kJ ( 585 kcal), protein 23.7 g, fat 49.7 g, carbohydrate 21.5 g, dietary fiber 8.0 g, 1.6 g water

• Minerals: Potassium 658 mg, phosphorus 358 mg, magnesium 176 mg, calcium 54 mg, Sodium 6 mg, zinc 3.3 mg, 2.26 mg iron, manganese 2.08 mg, 0.67 mg copper, selenium 7.5 ug

• Vitamins: Niacin (B3 ) 13.53 mg, pantothenic acid (B5 ) 1.4 mg, thiamine (B1 ) 0.44 mg, pyridoxine (B6 ) 0.26 mg, Riboflavin ( B2) 0.1 mg, folic acid (B9 ) 145 ug, Vitamin E 6.93 mg

• Amino acids: arginine, 2.83 g

Ripe peanuts can be eaten raw, eaten roasted or boiled. The peanut has 24 percent protein content has a high nutritional value. With 176 mg of magnesium include peanut, in addition to the cashew nuts to the magnesium-rich plant foods. In particular, in a vegetarian diet can be the peanut make a valuable contribution. However, peanuts also contain relatively large amount of phytate, which restricts the absorption of minerals contained. Worth mentioning is the very high arginine content of peanut products.

Health hazards

A representative study in the United States in 2003 found that about 1.2 percent of the population are allergic to parts of the peanut. This result is consistent with another study from the year 1997. Compared to other foods, the allergenic potential of the peanut is relatively high. This is due to the high number of peanut allergens.

The symptoms of acute peanut allergy are very different, but often are hives, watery eyes or difficulty in breathing. In rare cases, the symptoms can also be very serious or even trigger anaphylactic shock.

Another problem is that peanuts under poor storage conditions of Aspergillus flavus, a mold that can be attacked, the toxic aflatoxin produced in peanuts. For this reason, strict import controls carried out both in the U.S. and in the European Union.

Trivial names

For the peanut or were the names Erdeichel, Erdpistazie and Mundubihohne common.