Page:Foods and their adulteration; origin, manufacture, and composition of food products; description of common adulterations, food standards, and national food laws and regulations (IA foodstheiradulte02wile).pdf/460

 Composition of the Dry Hickory-nut.—Edible portion, 37.8; refuse, 62.2.

Water,                    3.7 percent Protein,                 15.4 " Fat,                      67.4 " Sugar and starch,        11.4 " Ash,                       2.1 " Calories per pound,     3,495

Peanuts.—The peanut is a widely cultivated plant. It grows extensively in the United States, and is especially regarded as a crop of high value in North Carolina and Virginia. Very large quantities of peanuts are grown in Senegal, in Algiers, in Egypt, and in many other localities.

The pod containing the seed grows underground, but is not a part of the roots, properly so-called. The pods are attached by a slender stems to the stalk of the peanut. The pod of the peanut matures underground, and it may, therefore, be regarded as the seed of the plant, entering and maturing underground. The seeds are immediately covered by a soft envelope and then by several similar coverings. For edible purposes they are much improved by roasting, which gives them an aromatic, nutty flavor which is much admired. A striking illustration of the peanut is shown in the accompanying colored plate.

Peanuts are used as food both directly, as after roasting, and indirectly, by the expression of oil, which after proper refining is considered of high value for edible purposes. The oil of the peanut forms an edible oil of rich flavor, pleasant taste, and high nutritive value. It is used, either alone or mixed with other edible oils, notably with olive oil for table purposes and for the making of salad dressing. The residue of the pressings for peanut oil are highly valued as a cattle food, containing large quantities of nitrogenous nutriment, and also as a manure.

The composition of the peanut varies greatly in different localities. Its chief value as a food material lies in the high percentage of protein it contains and the high percentage of fat. The composition of the typical hulled peanut is shown in the following table:

Water,                    9.2 percent Protein,                 25.8 " Fat or oil,               38.6 " Sugar, starch, etc.,     24.4 " Insoluble cellulose,       2.5 " Ash,                      0.9 "

Only the blossoms which form on the lower part of the stalk produce the fruit, since it is necessary that the long stem should strike the earth and the young fruit penetrate to the depth of from five to six centimeters in order that the fruit may mature. This method of penetrating the earth is shown very well in the colored figure already mentioned.