Peanuts are actually legumes with a nutlike flavor. They are sold in the shell or shelled; whole or in halves; raw or dry-roasted; and unsalted, salted, or only lightly salted. Dry-roasted peanuts, which have not been cooked in oil, are preferred in Asian cooking. The Virginia variety of peanut is longer and more oval than the smaller red-skinned Spanish variety.
Peanut butter is principally used with jelly, jams or preserves, but may also be accompanied by honey, bananas or marshmallow cream to make a “Fluffernutter” sandwich. Commercial peanut butter principally uses partially hydrogenated oil to give it creamy consistency. This introduces a high level of trans fats into the spread. Some ‘organic’ varieties have replaced that oil with palm oil, which is not hydrogenated, but causes other harmful effects. The safest peanut butters are those with no added oils, and only contain peanuts or peanuts and salt. These may require stirring to make them spreadable.
The peanut, or groundnut (Arachis hypogaea), is a species in the legume or “bean” family (Fabaceae). The peanut was probably first domesticated and cultivated in the valleys of Paraguay. It is an annual herbaceous plant growing 30 to 50 cm (1.0 to 1.6 ft) tall. The leaves are opposite, pinnate with four leaflets (two opposite pairs; no terminal leaflet); each leaflet is 1 to 7 cm (⅜ to 2¾ in) long and 1 to 3 cm (⅜ to 1 inch) across.
The flowers are a typical peaflower in shape, 2 to 4 cm (0.8 to 1.6 in) (¾ to 1½ in) across, yellow with reddish veining. The specific name, hypogaea means “under the earth”; after pollination, the flower stalk elongates, causing it to bend until the ovary touches the ground. Continued stalk growth then pushes the ovary underground where the mature fruit develops into a legume pod, the peanut – a classical example of geocarpy. Pods are 3 to 7 cm (1.2 to 2.8 in) long, containing 1 to 4 seeds.
Peanuts are known by many other local names such as earthnuts, ground nuts, goober peas, monkey nuts, pygmy nuts and pig nuts. Despite its name and appearance, the peanut is not a nut, but rather a legume.
Peanuts have many uses. They can be eaten raw, used in recipes, made into solvents and oils, medicines, textile materials, and peanut butter, as well as many other uses. Popular confections made from peanuts include salted peanuts, peanut butter (sandwiches, peanut candy bars, peanut butter cookies, and cups), peanut brittle, and shelled nuts (plain/roasted). Salted peanuts are usually roasted in oil and packed in retail-size plastic bags or hermetically sealed cans. Dry roasted salted peanuts are also marketed in significant quantities. Peanuts are often a major ingredient in mixed nuts because of their relative cost compared to Brazil nuts, cashews, walnuts, and so on. Although peanut butter has been a tradition on camping trips and the like because of its high protein content and because it resists spoiling for long periods of time, the primary use of peanut butter is in the home. Large quantities are also used in the commercial manufacture of sandwiches, candy, and bakery products. Boiled peanuts are a preparation of raw, unshelled green peanuts boiled in brine and often eaten as a snack. More recently, fried peanut recipes have emerged – allowing both shell and nut to be eaten. Peanuts are also used in a wide variety of other areas, such as cosmetics, nitroglycerin, plastics, dyes and paints.
Peanut oil is often used in cooking, because it has a mild flavor and a relatively high smoke point. Due to its high monounsaturated content, it is considered more healthy than saturated oils, and is resistant to rancidity. There are several types of peanut oil including: aromatic roasted peanut oil, refined peanut oil, extra virgin or cold pressed peanut oil and peanut extract. In the United States, refined peanut oil is exempt from allergen labeling laws.
Peanut flour is lower in fat than peanut butter, and is popular with chefs because its high protein content makes it suitable as a flavor enhancer. Peanut flour is used as a gluten-free solution.
Boiled peanuts are a popular snack in the southern United States, as well as in India, China and West Africa.
Dry roasted peanuts
Dry peanuts can be roasted in the shell or shelled in a home oven if spread out one layer deep in a pan and baked at a temperature of 350°F or 177°C for 15 to 20 min (shelled) and 20 to 25 min (in shell).
To toast peanuts:
Spread the peanuts on a baking sheet and place in a preheated 325 degrees F (165 degrees C) oven. Toast, shaking the sheet occasionally, until the peanuts just begin to change color and are fragrant, 5-10 minutes. Remove from the oven and let cool to room temperature.
To chop peanuts:
Spread the peanuts on a work surface and, using a chef’s knife, chop with a rocking motion. Or, chop the peanuts in a food processor fitted with the metal blade; do not overprocess or the nuts will turn into a paste.
For other nut varieties, see almonds, Brazil nuts, candlenuts, cashews, chestnuts, hazelnuts, macadamia nuts, pecans, pine nuts, pistachios, and walnuts.