PEANUT (Ground-nut, Earth-nut, Pistache de Terre, Mon key nut, Goober, Manilla nut), the fruit or pod of Arachis hy pogaea (family Leguminosae). The plant is an annual of diffuse habit, I to 2 ft. high, with hairy stem, and two-paired, abruptly pinnate leaflets. The pods or legumes are stalked, oblong, cylin drical, about I in. in length, the thin reticulated shell containing from one to three irregularly ovoid seeds. After the flower withers, the flower stalk has the peculiarity of elongating and bending down, forcing the young pod underground, and thus the seeds be come matured at some distance below the surface. Hence the spe cific and various vernacular names of the plant. Originally a native of South America, it is extensively cultivated in all tropical and sub-tropical countries. The plant thrives in a light sandy soil, and is very prolific. The pods when ripe are dug up and dried. The seeds are largely eaten fresh in tropical countries ; when roasted they are used in various ways for food. The seeds yield a large quantity of oil, which is used by natives for lamps, as a fish or curry oil and for medicinal purposes. The leaves form an excellent food for cattle, being very like clover.
Large quantities of seeds are imported to Europe, chiefly for the oil. The seeds yield from 42 to 5o% of oil by cold expression, but a larger quantity is obtained by heat, although of inferior quality. The seeds being soft facilitate mechanical expression, and where a solvent is used, a very pure oil is obtained. The expressed oil is limpid, of a light yellowish or straw colour, having a faint smell and bland taste ; it forms an excellent substitute for olive oil and is used in various food preparations.
In 1925 the principal countries importing peanuts were: France, 1,503,887,000 lb. ; Germany, 713,245,000 lb. ; United Kingdom,
335,004,00o lb.; Netherlands, 229,540,00o lb.; and the United States, 120,158,000 pounds. The chief exporting countries were: British India, 1,036,670,000 lb. ; Senegal, 985,409,000 lb. ; and China, 530,227,00o pounds. The principal countries exporting peanut oil were: China, 78,408,00o lb. ; France, 53,744,000 lb.; Netherlands, 26,336,000 lb.; and the United Kingdom, 25,431,00o pounds. The chief importing countries were : Netherlands, 40,209,00o lb. ; United Kingdom, 25,148,000 lb. ; Algeria, 23,542,000 lb.; Germany, 23,016,000 lb.; and Canada, 16,134,000 pounds.
Since 190o, when the annual production was about io0,000,000 lb., peanut culture in the United States has very greatly increased. In 1927 the total crop, grown on 1,128,000 ac., amounted to 806,990,000 lb., valued at $32,501,000; 8o% of this yield was produced in four States—Georgia, North Carolina, Alabama and Virginia, ranking in the order named. The value, in 1925, of the products of the peanut roasting, shelling and cleaning establish ments was $20,623,810. Throughout the country roasted peanuts, which are eaten out of hand, are everywhere sold in confectioners' shops and by street venders ; peanuts are also extensively used in making various confections. Since 1900 the food preparation known as peanut butter has become increasingly popular and is now regularly sold by grocers ; the value at the factory of the peanut butter produced in 1925 was $6,200,547. The consumption of peanut oil for food and other purposes exceeds the supply available from domestic crops, resulting in extensive importations of peanuts for oil-extraction.